Wish I could get a new one...........
Thanks to all who replied with helpful suggestions. First let me say that I would love to purchase a new unit but unfortunately I'm dealing with all newly replaced cabinetry which I don't want to redo and none of the new models fit the opening. (Any one aware of one I've missed? Cutout dimensions for frig:
26 & 1/2 H x 21 W). Did find an icebox @ Vintage Trailer Supply that I think will work but that's my default choice if all else fails.
So at this point, unless this thread bears additional fruit, I'm going to pull the unit, try cleaning burner and flu as suggested. I've never smelled any ammonia but the leak may have been long ago. If that doesn't help will next take it to RV Doctor George in Sacramento to see if an adjustment will bring it back to life (his suggestion and the only person willing to even look at it so far). My intuition tells me that it probably won't and unfortunately he said he doesn't have any replacement parts for it in his junk yard so if he can't get it cooling and there are no other leads from this thread I'll be calling Leon in Indiana. Obviously I'd be thrilled to find a resource a little closer to home, somewhere in Nor Cal or at least the Pacific Northwest.
Thanks again for your help!