There has been a lot of buzz on other sites about BFG being discontinued. How these stories get started is usually fueled by back order status on certain sizes. BFG has published comments that they are not discontinuing the T/A line and they are simply behind on production on some of the less commonly ordered sizes. Back log is expected to be gone and dealers fully stocked in 4-6 weeks.
In the mean time, there are Coopers, Goodyear, Hoosier, McCreary, Mickey Thompson, Dunlap, Michelin, and a host of others that offer various 15" sizes. If you intnetn on getting speed rated tires, there are a couple of English manufacturers that are offering wide sizes in dot approved Z rated 15" tires. Just be prepared to fork over some serious cash if you want them.