I just wanted to update this thread. I picked up the Hankooks RA08s that Russ linked to earlier. I picked them up at $69.00 each, which was a steal! I had some Kumho Solus P205/75/15 tires on there and it was a bit wobbly. They worked, but I was never able to find the appropriate "stock" sized tire with load rated side walls. Russ's question got me looking and for being .4% off, I thought that was good enough for me.
So far they have been great and the ability to corner has drastically improved.
If anyone is looking for 15" bus tires, the Hankook 195/70R15s are the way to go.