Originally Posted by Salamandrine

Yeah, I'd ask the shop first. it used to be bad form to bring your own parts to a shop, but that's mostly changed now. You'll need a 27" rim, which is a bit archaic but there's still some around. Have a look at the sticky thread above.

Your bike appears to be a 1977 Super Mirage. The combination of color, cable stop location and 2040 tubing narrows it down to that year. There's a catalog out there somewhere.