Listees,

I've answered my own question as to the difference between the different
size front axle spindles in the VW parts catalog.

It's really quite simple once I figured out the VIN system.  It seems that
in 1984 the spindle diameter was increased from 19 mm to 22mm beginning
with 1984 vehicle number 023828.  Since my van was made in 1985 it is clear
that it was built with the 22 mm spindles, and therefore the speculation
that the right front had been replaced with an older one appears
correct.  For preceding years the parts catalog shows that the newer
spindles can be used on older Vanagons as well.  The part numbers in
parentheses are the older parts shown for reference purposes.

I still think the mechanic should have noticed the discrepancy, but all's
well that ends well, and the matter is over -- even though I had to shell
out another $50 to have the correct bearing put in.

By the way, if you want to interpret your VIN click on
http://vintagecars.about.com/autos/vintagecars/gi/dynamic/offsite.htm?site=http://www.driversfound.com/gak/vininfo.htm
It has all of VW's models and an explanation of their VIN's.

Charles
'85 Westy