The wheels are 451's with Durano's to fit.
I found them through a supplier in Taiwan that sells here via YahooAuctions Japan. They're an 'off brand' of some sort - "Rotaz", but have a nice build, weight, and quality.

http://page7.auctions.yahoo.co.jp/jp/auction/g75716837

Here's from the listing:
1223grams (pair)
6061/T6
CNC Sidewalls
Swiss spokes: Front/Rear 24
Lightweight hubs *I did some digging on the net, and they're the same as the older AmericanClassic's.
Front 100mm, Rear 130mm
Shimano 8-10sp compatable

Not a bad deal for the price!
(I'm even tempted to buy another set for a future build I'm so satisfied)

Also, the freewheel has a nice smooth sound to them. : ) Not loud'n w/few clicks - but quiet'n w/alot of clicks. ~ something about the freewheel having plenny of teef's. Kinda makes a swishy sound, rather than a clicky sound..which I like.

They were shipped straight out of Taiwan, not from Japan..if that's of any importance..

Rgds,
K.

- a few pages ago in this thread I wrote I had ordered a pair of "Xero" 451 rims, but I heard back from the shop, and the manufacturer said they weren't sure if they were going to continue w/them, so I canceled & found the above.