Technics SP-10 MKIIA tonearms

An SME 3009 will fit (I have two of those on Obsidian bases, as the SME was popular in professional use, if you could not afford the EPA 100.) I don't see any reason why any 9 inch arm would not work. Longer arms might fit, if they don't have a large mounting base or plate. Anything longer than 10 inches probably won't make it. At least with the original armboard, as it has a metal rim, which takes up real estate.
The EPA 100 is still the best arm you could put on that combo given the price. If you want to use 12 inch arms, OMA make slate plinths all the time for the SP10 that can accommodate any arm.

Jonathan

A.J. Van den Hul uses the EPA 100 everyday on his SP10. We've talked about this combination a number of times over the years. He can have whatever he wants. That's what he uses. And since he builds carts, maybe he knows something?

Jonathan

The original armboard is veneered plywood in a metal frame. If you would like, we can make a slate armboard, or any other material, to replace the original. I would think the slate would be an improvement. It would be a simple matter to make a new wood armboard, and any competent woodworker could do that for you.

Jonathan