After a few weeks of frustration, the fill valve is repaired, and there is
now a full tank of propane.  The local propane company did the work.  They
were able to obtain an o-ring kit (part number V20128) from Manchester Tank
for the autostop valve (model 430).  I'm passing this information on in case
anyone else finds themselves in the same position.

A new tank would have cost $289 (plus installation).  The repair cost $64
and included the propane.

Ellen
Lola, 1985 Vanagon ASI conversion