All sounds goog.
We have a Motorsport Tyre place up here that sells us used 13" Slicks that have pretty good life left in them for $50 ea fitted. As for the 10" ones, unfortunately you are in the same boat as me, have to buy them new, best I can find is around $200 ea.
You should ask around the Motorsport Tyre places down your way if you have them and see what they can do for you.
Hope this helps.

Thanks

Ian