No, not really worth it. The only things there of any use are the body, WLF, and the 120 back. 250CAD sounds a bit much for that these days. You still need a clean lens and have the 120 back serviced. Say another 150-300, depending on the lens. If you're a do-it-yourself kind of person, you could clean up the back yourself and get some seals cheap; cleaning the lens has its own drawbacks. And as fmajor said, who knows how much fungus could be residing in the camera body?
I just paid $300US for a Pro-S, 90mm C lens, and two 120 backs, all clean and in good condition, ready to use. I may have overpaid, but not by much.