Need help please!

[jacksonuga]

I know I could probably find this answer after searching and searching. I've been through a lot of crap with the parts stores and really just need a simple answer please! I am doing the ECM upgrade on my 85 base corvette. I have bough everything needed except the PROM. I ordered one two weeks ago only for the parts store to tell me the order was canceled a day later! Incompetent people! Now it could be another two weeks before I get my prom. I have the moates apu1 setup and am ready to fix my car.
My question is, do I have to have the exact prom for my car to start with? Or can I just use one that is compatible with my new ecm? I'm gonna put a cusom tune on it anyway, right?
My car calls for an AANM prom which seems to be pretty rare. Can I use an ARAP or anything else? I have several new blank chips ready to burn. Unfortunately the one thing I don't have a lot of is time! I'm a full time single father with rare weekends to work on my car, and I had been planning this for awhile! Stupid parts store!