15" speed rated tire ?

[R67Chevelle]

Heres my second post so lets see how this goes. On my 67 chevelle I am going 15X10 rear and 15X8 front weld racing draglites. I have always liked the 15" look and even though 17 & 18's are nice I really like this look of wheel on my chevelle.

Now heres the tough question. I have had 295/50/15 & 225/50/15 BFG's which I dislike the ride, performance, and its low speed rating. I was wondering if any tire manufacture makes either a Z rated tire or simular speed rating, high performance tire in this 15" sizes. I have tried as many sources as I know of, so any advice would be greatly helpful...

Also, I have emailed BFG and goodyear about this situation without any responses... Thanks...