Since you have most of the kit I would hang them up and Try to find the rest. I don't see why you couldn't put a set of bombardier tracks on them too. They might be easier to find. I know I keep stuff for years and as soon as I sell it I'll find the rest of the parts for it a couple months later. I seen a set of tracks off a bombardier with rotten rubber basically going for scrap on CL about 6 months ago. They were with some cultivator parts and he had no idea what they were for.
Here's what the bombardier tracks look like on my ford 4000