A long enough boring bar would be ridiculously expensive, although maybe you can get an extension for those too. 1" or 1 1/8" is a little on the small side for a long boring bar.

I think the part that would cost on the fork fixture Alex made is the dummy axle holder. If someone has a mill, that wouldn't cost much, but otherwise it would probably cost as much as the rest of it. Depending on what you had the plates made out of, I'm guessing one of the online laser cutting places would charge about $100. Not sure what 80/20 charges. So $200 is about right. An angle plate like I have is about $50 if you catch them on sale.