Ultegra wouldn't work as they're 32 -spoke only. For Shimano hubs, you'd need to go with Dura-Ace. For DA hubs and black CX-Rays on a set of these rims, you're looking at £680 delivered. With Sapim Laser spokes and Race on the rear drive side, £600.
Cheaper hub options - Miche Racing box (silver) or Miche Syntesi (black) come in 24/28 sets and built with Laser/Race spokes would come in at £376 or with CX-Rays, £450.
Ultegra wouldn't work as they're 32 -spoke only. For Shimano hubs, you'd need to go with Dura-Ace. For DA hubs and black CX-Rays on a set of these rims, you're looking at £680 delivered. With Sapim Laser spokes and Race on the rear drive side, £600.
Cheaper hub options - Miche Racing box (silver) or Miche Syntesi (black) come in 24/28 sets and built with Laser/Race spokes would come in at £376 or with CX-Rays, £450.