For anyone looking for some 630/27" rims can find current production rims from Velocity. They make their Velocity Synergy and Velocity Aero rims in 630 in a variety of drills. The Aero is available in 32h, 36h, and 40h while the Synergy is available with 32h, 40h, and 48h. The Velocity Dyad is currently out-of-stock for 630/27" but I've heard another production run is being contemplated.

However, most of us don't have any skin in the game of whether the current distribution channel offers a stockists dream of 630/27" rim offerings. The reality is that high quality rims are always available on eBay or via swaps.

You can always find quality Mavic, Weinmann, Ridiga, Exal, Velocity, even sometimes Campagnolo rims in the 630 size, and often NOS. Most of us don't need thousands of rims, just several. There are always high quality tires available.

I've never understood the point of converting to 700c. The bike rides less smooth with the marginally smaller BSD and the frame wasn't built for that wheel size. In terms of giving a smooth ride, 630 will always offer a smoother ride than 622/700c for a given rim/spoke tire model/pressure set-up, when all things are equal. Is not a HUGE difference but its noticeable. Think the difference between a 559/26" mountain bike setup and a 622/29er setup, only on a smaller scale.