Try Hands on Optics. You should be able to get a pair for about $30. BTW the prices listed on the web site are wrong. I got a pair of 5.7" rings from them for less than $35
Also take a look at Orion. They sell rings very cheaply but only have a few sizes.
Darren in Bakersfield
_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo