Andy, thanks for taking the time to post your in-depth response! It's really helping me wrap my head around all the different aspects, including some (like brake hole distance) that I had forgotten are very important. I will try to get a few 'hello world' posts in the newbie section so I can actually post links/pictures to help with my explanations, as I'm sure I will butcher terminology here and there along the way.

Right off the bat, I'm hoping that this will be easy rather than stressful. My goal with this project is simply to have my bike operational and roadworthy again. If it doesn't handle 100% the same as before that is okay, and I will just use it as a daily reminder to be a little bit more present while I'm on the beast

With that, I started at step 1 and just sized/took measurements of everything Andy mentioned below:

• Steerer length: 8 11/16"
• Steerer diameter: 1"
• Length of threading: 35mm
• Crown Race ID: 27mm
  • This I determined through a combination of measuring a dozen times with a mm ruler, as I don't have a caliper & I also found what appear to be identical NOS headsets [it is a 'Hatta Vesta' headset] available for sale online with the crown race ID listed as 27mm to back up the measurement
• Brake Hole (center) to Crown Seat: 1cm
  • This is less if I measure from the top of the brake hole, but I'm assuming measuring from the center here is the correct way to do it
• Caliper Reach: 39-49mm
  • As with the Crown Race, I found an identical component (Suntour Cyclone, though this is the black version that came standard with the '86 Club Fuji) on velobase in order to back up my measurements here. It's not a long-reach, for sure. It also might not be the CB-7100 listed on velobase, but I can't find anything that's closer.
• Using your measurements it seems like I'm looking for a fork in the range of:
  • 311mm (of my 700c) + 39mm (to 49mm of caliper reach) = fork length of 350mm-370mm A-BH?
• Rake: This measurement is not exact, but I believe the rack distance to be about 45mm, right in the range that you described
  • The reason I say it's not exact is because both forks are twisted. However, the right fork twisted where the fork meets up with the steerer tube near the brake mount, and I believe it is still fairly true to the original line below that bent spot.
  • A second question on rake: what kind of difference does the shape make? In reading an article on trail it seems that blade shape won't make a difference to how the amount of trail affects handling, but am I right in thinking that a curved blade might absorb more road vibration than a straight one?

Andy I totally agree with you on looking for new vs used after spending today thinking about it. I could likely find an exact match online and steal the fork, but that feels disrespectful to the other bike's potential to be someone else's escape, so I don't feel right going that route. I also don't want to go the used route, for exactly the reasons you mentioned, primarily that I'd really like to make sure the new fork is road-worthy. I've got almost my full range of motion back in my arm now but am not too eager to repeat the experience!

In Sum:
I'm now hunting for a new fork. It needs to be a 1" threaded 700c fork with 350-360mm of length from the axle to the brake hole, ~45mm of rake, and standard 100mm axle spacing + 9mm dropouts. Also, I took a closer look at the "sealed" bearings I was worried about; turns out they're not actually "sealed" (as in cartridge) bearings, they're loose bearings held in place by a metal bracket-like device pressed into the race; very interesting.

Further Q's if you've time:

• I'm going to check out a LBS or two in-person to see if they'd have ideas on sourcing/pricing, but if it ends up being less expensive to buy online I will likely go that route instead. Do you have any online stores you'd recommend for sourcing a new fork? I'm not familiar with any of the online stores I've found so far unfortunately, and want to make sure I deal with a reputable source if I take the online route
• As above, does the shape of the rake affect any ride factor? I imagine a curved blade will absorb more road vibration than a straight one, but I'm here because I'm not as smart as all y'all are
• The bearings: I like 'em! Is there a reason I shouldn't? I could easily pick up new 5/32" bearings (these have been measured as well) from somewhere, but neither the bearings nor the races appear to be in bad condition at all, really. My inclination is to just re-grease these bad boys (I've already cleaned them) and put them back in place on a new fork. Sound appropriate?
• Lastly (I promise!) it looks like some online sources I've found just list the steerer length (to the crown seat) and then a '700c' size - is it safe to assume that'd fit, or should I not take any chances and make sure I can find all the measurements available if I'm buying new online?

If you made it this far you deserve a medal, I've been chipping away at this bit by bit all day long. I'll get some newbie posts in so I can share photos of the damage & destruction as well as the unique (to me) bearings.

Thanks again for the time and for taking a look!