It really would be cool if someone could start making these. I know the jets vary over the CB years, but this particular style jet is the only piece in the cylinder head that's no longer made by Honda (aside from the casting, of course) or anyone else.
The guy at the shop told me that I'd need a new one because the old one had been lost. I'm almost certain I had both jets when I dropped it off at the shop, but I have no way to be sure. Anyway, when the shop owner mentioned one had been lost, I thought, oh no problem, I'll just have to get another. I didn't realize the part was unobtainium was flybox says. Otherwise, I'd have taken them both out before leaving my head with the shop.