Snes Sram and Eprom Questions

Hello there guys, how are you.

If I take a donor cart, with a mad-1, and 16Kb of sram.

Question 1) Can I use it to make a game that does not use sram? with 2 eproms + 74htc139?

Question 2) Is it possible to make a game with 2 eproms, if the donor has NO mad-1 ? If so, do I still use 74hct139?

Question 3) I made 2 games with 27c801 (1 mega byte) this eprom is expensive, any other cheaper alternatives? if so, what's different about the procedure?

Thanks so much guys!

You're paying a premium for old DIP parts. Unfortunately, modern parts are all surface-mount. (q.v. http://www.findchips.com/search/m29f800*, http://www.findchips.com/search/m29f160* )