Russia AC-4c tires

I have not been able to locate the yahoo ac4 group nor further
information about tires. Someone told me that there is a Russian
language site for Aviastroitel - does anyone know how to find it? As
an alternative, I have found an 8" dia plastic hub wheel that may do
the job. It looks like a lawnmower wheel, and has a weight limit of
55 lb. I am thinking that some bearing sets from roller blades can be
inserted in the hub (some machining needed). The weight would be
about the same as the original wheel (24 oz.). Does anyone have
advice about this?