I have hall generators (or senders) for $99.  They come with that plastic plug that attaches to the side of the distributor, the hall sender and some shims and clips.  Please specify what year Vanagon you have when ordering as they are different between aircooled, 83.5-85, and 86-91.  Made by Bosch.

Thanks,
Ken Wilford
John 3:16
www.vanagain.com
Phone: (856)-765-1583
Fax: (856)-327-2242