I believe the dealer has a 'fix-it' kit for this that includes both valves and the crossover hose that connects them.
When I got this a couple of years ago it was about $27.

Todd
'88 Westy

KENWILFY@AOL.COM wrote:

Andrew, I was not aware that these valves ever went bad, however here are the
part numbers and prices:
251 201 311A- float valve- $12.30 (one per side)
N 901 005 01- gasket for float valve- $6.20 (one per side)

I can get them if you need them.

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