I would go to Kmart and buy one of theirs for $5 each.  They look very
similar to stock (except they have a little imprint of a cup on them so blind
people will know what they are- my only guess) and they also have the nicer
setup of two fingers to clasp the cup rather than the single ring.  I like
the two finger deal because it is adjustable (I can put a big sized or
smaller sized drink in there) and it also holds the drink very firmly (my
stock one kept allowing my coffee cup to escape while going over train tracks
or pot holes).
The quality level  seems to be the same as stock and it is much cheaper (you
can buy enough to put all over the van for the price of one normal one).
So if you can't get one from your local Kmart, please let me know.  For $5
each plus shipping I'll get you some from my Kmart the next time I'm in town.

You will thank me later,
Ken Wilford
http://www.vanagain.com
John 3:16
Phone: (856)-765-1583
Shop:   (856)-327-0027
Fax:     (856)-327-2242