AC Heater Core Replacement Source?

[Rich72C10]

I think I am having a leak on one of the hose connections to the AC Heater core (the one coming from the block). It acts like the hose is loose but I think it is the inlet. I loosened the clamp up, pulled the hose, put it back on and clamped it down. Pretty sure it can't get any tighter but still leaks. Hose is more or less new, so it is not split that I can see.

Anyways, I have already read up on how to get it out for replacement - looks like fun. But I want to find a good source for a replacement, sadly GMC Pauls seems to only have the non-AC Heater Core. I have read that "Mexico Made" or "Part Store" AC Heater Cores do not fit properly.


Soooo, any one have a current good source for a AC Heater Core for a 72 C10 original AC setup?

Thanks!