Depends on what kind of "conversion" kit you buy, and whether or not you reuse the factory barrel or not. I have a Nordic kit with a Jim King barrel that is basically a customized 16" Ruger barrel threaded and has the A2 flash hider and front sight, and fat M4 handguards and rings...the only thing I used on my original 10/22 is the receiver and trigger group.
If you are going to be going a similar route, buy the cheapest 10/22 you can find.