There is company in Germany that has a conversion kit. The price is approx.
$6k US. This is complete with everything needed including better brakes. (
kit parts can be bought separately)
The standard price of the motors are $4k-$5K(used) and you have to make sure
you have the complete harness and all accessories.

 I would like to find someone on this list who would spend 10k+ on their
vanagon.

My decision was to put a Subaru 2.2 in my 84. The complete engine ia approx.
$1k-$1,500.
The Kennedy kit is complete at approx $1,500. Automatic is about $1,400. 

$3k + my labor + another $500-$1k for additional work that should be done to
any used engine and parts that should and could be done on the van at the
same time.    

This I consider reasonable for 135hp in 16v motor with a modern fuel
injection system & ignition system.

My van should be finished in a couple of weeks. If anyone wants a test
drive, I'm on Long Island. (Near NYC)

just my $1.00 worth

Steve