Sorry about the late response to your inquiry on raingutter trim.  I was
in at GIJoes today (a northwest sports/auto store) and saw two different
flavors of vinyl trim which is marketed for use on truck door edges.  It
would work perfectly for replacing the vanagon rain gutter trim and is
available in 23' lengths for around $12.  They had both chrome and black
gloss.
Didn't get the manufacturer name, sorry.

Happy Holidays,
Brent
www.weidefamily.net/vanagon