Very well, you've got twelve months. If you can do it and make it look good I will offer some handsome vintage Technics gear in trade to do the same for me. I suppose we're getting off track of the original post. PM me for details.
The SP-10 Mk II has a more powerful motor in torque. It has a heavier platter, and a separate power supply. It cost $2800 US new for the motor unit. The SP-15 and SP-25 give the same performance, but have motors closer to the SL-1200 type. They were less expensive, but still broadcast grade quality all the way and sold to that market mostly. The SP-15 has 3 speeds, the SP-25 has two speeds. All 3 in nice condition are superb turntables.