Regarding rear braking, everybody’s leaning on just one side for sprocket and brake. Either called Sprockster, or brake/sprocket, installed right or left, may models are already available. But this one from Kustom Tech is a little bit more minimalistic with more groove details in the 2-piston caliper that you may like.
Available for 3/4″ or 1″ rear axle in a 51- tooth stainless steel sprocket, with welding tap and all the hardware included. Kustom Tech Italy.