Yeah, that was going to be my suggestion as well (though I wasn't 100% positive it would work with the superpass 2 (I think it mentions in the instructions about using a supercard to store the gba/.sav files), but it makes sense that you should be able to use any media with SRAM capability.
So if you have already flashed your supercard bios using the included programmer, you can give that a shot, and let everyone know if it works...
BruceG