Where can I buy 50mm ID velocity stacks

Looking for four 50mm ID, 60-70mm tall, 80-88mm max bell OD stacks for a ITB setup Im working on. They can not be flanged or threaded either.

I found some at http://www.velocity-of-sound.com but they are in AU, which isnt a huge deal other than the 7-15 day wait. If I dont find something closer I will probably jsut buy from them.

I just thought maybee there was a place state side that I could get them for a reasonable price (25-30 ea).

Thoughts?

Dan