Nice! Yes, those tanks -- that looks like a Heinrich -- do fetch a lot of money.
Also, I was saying that you had an R50 based on that first photo and the 6-finned valve cover, plain collar exhaust nuts and round profile cylinder fins. (That last detail eliminates the R60/2.) But the motor you show above looks like an R69S motor, with the 2-finned valve cover and finned exhaust nuts. The engine number or a measurement of the bore will tell all.
If the parts of the bike came from the factory together, then the frame and engine numbers would match. I'm betting they don't however, based on what I'm seeing in your photos. The motor is a mid 60s model, with the early style front cover and a later style timing chest with a separate oil pump cover (that could be replaced with a tach drive cover) -- right where it's resting on that die. The two final drives are early, no later than 1961, as they have no vents at the top. (Can't tell about what's on the bikes in the two photos.) And the frame, unless it has been messed with, is also early, no later than 1961 or 2, as it doesn't have the reinforcing gussets where the vertical tube meets the bottom tube.
The trans is indeed correct for your /2. You will want to find a final drive that has a ratio that matches your motor.
