I think dtaylor is absolutely correct - the requirement is for a 35mm
film camera, and that's a common requirement for photography schools. In general usage, "full frame camera" refers to a dSLR with a sensor that's the same size as 35mm film, but "35mm camera" means actual film.
So, you should be able to find good deals on film cameras on Craigslist, eBay, etc. One thing to consider - you can get any old film camera, or consider an EOS film body (even a old Rebel film camera) to satisfy the requirement, which means EF lenses would work on both.
Assuming it is a 35mm film camera you need to meed the requirement, you'll obviously still want a dSLR for some of your shooting.
If you're set on the 7D, I assume you also looked at the EF-S 17-55mm f/2.8 IS. IMO, that's the best general purpose zoom for a crop body, with a decent aperture and the benefit of image stabilization. It's also sharper than the 17-40mm f/4L when used on an APS-C body. The only downsides to the 17-55mm is that it's not weather-sealed (which the 17-40mm is when used with the partially-sealed 7D), and incompatibilty with FF (which is very relevant to you if you're getting an EOS film body!). So in your case, the 17-40mm makes more sense than for most crop body shooters.
Two more considerations:
1) When learning about photography, one of the creative elements you'll work with is depth of field - both deep and shallow. Deep DoF is relatively easy to achieve (inexpensive P&S cameras have it), but a shallow DoF will be difficult to achieve with an APS-C camera and an f/4 lens like the combination you're considering. So, I'd strongly recommend you consider a fast prime lens. There's the 'nifty fifty' (EF 50mm f/1.8 II) as an inexpensive option. If your budget allows, consider the EF 85mm f/1.8 - that will give you a telephoto lens plus a fast lens, allowing work in lower light (where the 17-40mm f/4 on a 7D will be not be very useful), and giving you a wide aperture for shallow DoF shots. As EF lenses, both would work on a film camera.
2) Get a decent tripod. That does two things, first, it improves IQ. IS in a lens can help, but there's no substitute for eliminating all the effects of shake from a shot. Second, it forces you to slow down and think about your shots. That's actually one reason why photo schools require film cameras - if you only have 36 exposures to work with, instead of a memory card that can hold 100-200 times more images with no associated developing costs, it forces you to think carefully about each shot before you press the shutter. Don't cheap out on this one. Read
this, for starters. If you balk at $1K for Gitzo legs + a good ballhead, that's understandable. As a compromise between quality and value, I recommend Manfrotto. I really wouldn't go much lower than that if you can help it.
Good luck!