Looks like a Bassani. Had one on a Suzuki TS250 that I dismantled and on a TS185. Shape of the header, and perforated sheet metal heat shields identify it. Popular in the 70's and regarded as a good performing pipe. This one may have had a repair on the end, as all the Bassani's that I have seen had a straight outer surface to the tail section with an internal/ no stinger.