Personally.... I would get something like these WTB KOM i23 rims , some mid-level Shimano or Novatec hubs, and then get them hand-built with either DT Comp or Sapim race double butted spokes.
I think @Howard or one of the other CX crowd should know where to get hold of Novatec hubs.
At risk of doing the classic forum move of just recommending what I've used, Bitex hubs are also a good alternative to Novatec. Sealed bearings, 54poe, centrelock, plus end caps are easily changeable. @hoops also recommends them I think
Personally.... I would get something like these WTB KOM i23 rims , some mid-level Shimano or Novatec hubs, and then get them hand-built with either DT Comp or Sapim race double butted spokes.
I think @Howard or one of the other CX crowd should know where to get hold of Novatec hubs.