My rear rim seems fine but spokes are breaking. I'm going to examine it all in more detail this weekend but, at the risk of getting ahead of myself, I'm wondering how difficult it is to replace the complete set of spokes. I know that I'll have to take one spoke off from each side and measure them so I get the correct length and I think I'll replace the nipples and rim tape at the same time. I do have a spoke wrench but I don't have a truing stand. My thought was to purchase the supplies, replace the spokes, semi-true it and then take it to my LBS for final work. One LBS just said, "buy a new wheel, the cheap ones are just $40 (CDN)" but I think I'd like better spokes than the cheapest ones you can get and, as I said, I think my rim is fine (I can't test truing right now because with 4 spokes broken, it is not true at all).

Thoughts?

All depends on the quality of the components you have. Replacing spokes is pretty easy but not if you've never done it. The $40 wheels are pretty crude but if that is what your local shop is recommending, perhaps they've made a judgement as to what you have now. Once several spokes have broken on a cheap wheel set it usually is time for some serious replacing. ON THE OTHER HAND building a wheel and having it work is pure joy! Be prepared for some frustration along the way. There are tons of videos showing how to get started. You could buy the cheap wheel and then have the time to play around with the old one.

One cause of breakage is low tension, allowing the spoke to flex and fatigue. Perhaps your wheel needs tensioning.

The bike is a 2002 Norco Bigfoot, certainly not much these days but it works well, even now so I'd like to keep it working well and a nice wheel would be, well, nice.

The LBS hasn't seen the bike yet, I just identified the bike over the phone and the fact that 4 spokes are broken. I could just replace those 4 but I thought this might be an opportunity to improve the wheel and possibly prevent or at least, reduce the change of near future spoke breakage.

The $40 wheel might work fine, but I'd ask the wrench at the LBS if he'd take $20 more to go over the wheel, make sure the tension is up where it belongs, stress relieve, and re-true if necessary. Tension and stress-relief can make even a cheap wheel last a long time.

Only a good idea if:
1. You have time to learn how to and then lace the wheel.
2. Don't expect to save a lot over having the bike shop do the whole thing.
3. Your hub is in good shape.
4. The rim has no impact damage (flat spots) and was in excellent true before the spokes broke.

Absolutely not - 4 spokes breaking is an indicator that more will do so.

Also not a good idea - a used wheel may have the same problem down the road, or other hidden problems, not necessarily easy to find one with the right rim and hub.

I would not think a shop would have to charge $20 to check/correct tension on a new wheel, but maybe so. I do think that's a good solution.

Looked at a pic of the bike. Looks like 36 spoke wheels. I would replace the spokes with double butted ones and brass nipples.