Scotty,
Just a suggestion if you can't find what you are after in 1/48. You could do a forced perspective diorama, which deliberately uses difference in scale to show distance and depth. If the A-10 is flying above the T-55, the tank should look a bit smaller, so by using a 1/72 scale T-55 (probably easy to come by), it would enhance the scale distance between the two.
I am sure some of the other guys here and in dioramas can tell you a whole lot more about this, but I have seen it done, and it looked really good. So you might want to at least keep it on the ideas table.
Good luck, mate
Matt