You can get new "tires" from Sew-Classic.com for $2 or under. I try to keep one on hand as I occasionally find a needy machine. They are cheap and rather plentiful. You got a good deal. It is a very pretty machine. My daughter has one like it.
Donna

For a quick treadle belt (because I couldn't wait to get one online) I bought aquarium tubing from the pet store - 6 feet for about $3.00. I cut to length, put electrical tape to hold the ends together (because I needed an extra hand LOL) then stapled the ends. Works like a charm. HELPFUL HINT: use clothespins to stop gravity pulling the belt back down the treadle belt holes in the top of the cabinet when you're doing it alone.