Although it's not an original Buffalo Forge machine, it maybe useful. I have one exactly like it except for the badging. Mine has a "Cummins Tool, Chicago Illinois" label. I bought it for cheap from a neighbor in 1979.
He had bought it the year before and then he and his wife decided to move to Oregon. The movers told he that he could throw it away here and buy another one when he got where he was going cheaper than it would cost to move it. I don't know how true that was.
I've had it in my shop since 1979. I haven't replaced anything on it. Same belts, chuck, motor, bearings. It just keeps working.
The slowest speed is 340 rpm. I've drilled 5/8 inch on the slowest belt position without any problems. There are two drive belts and changing speed is a little more complex than with a single belt machine.