Regarding the GPIB bus, every card compliant with its IEEE standard must be compatible.
Regarding the API software (probably you are thinking of accessing that card from LV using the same functions) the chances are reduced (the other company should provide GPIB libraries with similar entries). You can check this
IEEE 488.2 Controllers for PCs , they advertise the LabVIEW/LabWindows compatibility (but I don't know how it's implemented). Anyway, you can access other boards via DLL calls or ActiveX but you need to change the code when changing the board.
If your own concern is the price, check ebay.com and you may have the chance to buy NI cards for a good price.
Good Luck
