I use steel pallet packing strap. I put it low in the jaws of a vice, dress one edge square using a file, and burnish with a screwdriver shank. It costs me nothing.
Re spokeshaves: there's spokeshaves, and there's spokeshaves. Cheap ones are more trouble than they're worth, with poor geometry etc, and no amount of tuning will fix them. Good ones, well made, well tuned, are brilliant. I have vintage Stanleys and an HNT Gordon; also some old wooden ones, and new one one I made under Claire Minihan's tutelage. They can all be tuned to do different things.