Denis, are you in the US? Actually the KTM 495s here don't seem to draw quite as much $ as they might elsewhere. For AHRMA Ultima class it technically wouldn't be legal since it cam with a front disc, and yet the 84 bike -with USD forks is!!..the 84 came with a front drum. That said, I have teched through more than a few "1982" bikes with a dual plug ignition, reed, and blue seat. The reality is that some are converted to drum brake.
BTW the speed record was 123.75 mph on a 1981 495-piston port bike. The 82 had the "pro-lever" single shock, and the 83 had a reed, and dual plug ignition-the 83 is reputedly the better engine of the era. great find !!!!!!!!!!!!!!!!