All separate cards. I do believe there are 5 different versions of the game including the sequel. Basically all the same but for different countries. The Japanese version is the only one that is slightly different the cop's uniform is different and has a revolver.
I tried to make one from a chd from mame, but it wouldnt boot in the games pcb. I was able to snag mine from ebay about a year ago and havent seen any since. I think the cf cards need to be 512 mb or bigger and formatted in fat16, but i couldn't get it to work