The best quality ujoint? For a 260? That's a little unnecessary seeing that the next step up is a 297/760 and the cheapest one of those is still beefier than the more expensive 260's.
Get Dana Spicer parts if you're looking for quality. If you're looking for something that will hold up a little longer get some shafts out of a '95 and use the larger ujoint. There is no send in putting CTM's in stock shafts.
As for door parts, I haven't the slightest clue. I just wanted to help out with the ujoint situation.