Looking for more advise on my 1980 GMC

[baboiler]

I am guessing within 2 years I'll need to replace both doors on my truck. I think the ones on it now are aftermarket. Starting to rust along the inside on the bottom of the door. These doors don't come together perfectly with the cab corners when shut and the doors look to be aligned pretty well. They pull away a little at the bottom back corners. Am i correct in assuming any of the aftermarket doors are probably going to have issues with fitting correctly?Should I be looking out west for some original stuff that is rust free? Are there any oem doors out there to be had?Should I be looking into another alternative? I have some time before it's a must for my truck but I'd like to hear any suggestions you guys might have for me.