If there's a Vista driver, that should work in Win7. If the Vista driver doesn't work, then you're stuck. You have two less than desirable solutions.
1: Install XP/Vista in a virtual machine, and use them for all printing
2: Get a new printer
Incidentally, this is why you stay away from cheap printers. Typically they're on the market for 6-12 months, and that's it. There will be minimal driver updates, if any, so unless they happen to come out around the same time frame as a new version of Windows you can just forget about any support on that new version.
My Canon ip3000 printer driver doesn't work in Windows 7. The Canon site doesn't specify a suitable driver. Is there any way I can get my printer operational, please?