If I can get a righthand slider cheaply enough, with the necessary
body section to graft into my RHD bus, I think I'll do it. Might mean
I have to beg, buy or steal a MIG welder...

Now, I have three offerings at the moment.

One is a 2-tone bus, same paintscheme as mine, probably same interior
trim-panel color too, but it's in Alabama. The seller wants $550s
shipped within USA, which sounds reasonable, given individual
component prices on TheSamba and the time needed to cut the body and
box everything up.

Two others, one in the LA area, are asking what I am willing to pay.

OK, as the whole doorjamb are rails will be installed, I think there
will be no compatibility problem with the newer door in an older van.
EXCEPT the center rail, the one which guides the back edge of the
door.

Does an 88 door have the same rear (center) rail and position as an
84? That is, will an 88 rail fit the existing but unused rail mount on
the 84, and will that rail then be in the correct position?