It's the out of production BUB 7 2-1 I got one on my R Model - Awesome pipe looks better than every other pipe out there IMHO as far as the flow with the bike, both head pipes are visible and properly curved, nice longer megaphone muffler with scarf cut end. Really picked up the mid & upper power on my R, loud but I repacked with SS Wool packing & fiberglass and quieted it down. I put a 4" BMW M3 SS & CF resonator on it now it sounds absolutely perfect.
After lots of research I ran across an article about the demise of BUB Industries after one of the Bonneville Salt Flats races they sponsored, and found Mr. Ramsey Mitchell B.D.I. BUB Exhaust in Grass Valley, CA Work 530-277-0003 Cell 530-274-0800 that was resurerecting the company. called him & he had one in NOS on the shelf - you could try him I don't know if he has any left but he had a black one a few years ago when I bought mine. They used to be on ebay, but haven't seen any lately. Good Luck !