Hi Sari
The 6503 is not a good choice! It uses unstrobed I/O. Unstrobed (static) DIO involves setting/reading digital lines by software command, that means that you don't have guaranted transfer rates (no onboard clock). This board is good for controling or monitoring switches, relays, lights and so on.
A 653x board is the right choice for higher transfer rates.
Luca
Regards,
Luca