WRT to rebuilds it would be worth comparing GEX and comparables with
what VWoA is offering. It is possible that GEX is superior it is
definitely cheaper - 1500 for the aircooled and 2000 for the water
(that through a dealer) direct from GEX would be cheaper.

In both cases dissassembling the engine components is not difficult,
but make sure that you a) take pictures of each stage of the
disassembly and b) keeps all bolts etc in marked baggies. The photos
actually help a lot in deciding where the maze of wires and tubes go.
Don't expect any manual to be as precise as your own notes, diagrams
and pictures. We did the procedure on an aircooled and it took 1 week.
Half the time was devoted to cleaning all the tin and related heating components
(something you wouldn't need to worry about). R/R actually took only
half a day. tetsing the fule system ie injection spray and related
components was something we set aside time for. This would cost money
if you ahd a mechanic do it. For us it was a learning experience. Believe me if the van is not your daily runner and you
have the space it is worth doing yourself. Once the engine is
installed you can tow it to a trusty mechanic to have the timing set
properly and checked for vacuum leaks and correct installation etc. The reason I suggest this
is for warranty reasons-putting the onus on the mechanic.

The savings are two fold- a) learning a lot more about your engine so
you have to rely less on mechanics in the future for basic work and
b) in replacing additional items that you would have a mechanic
normally do ie
clutch, pipes trans. fluid etc.

DC