"- way too expensive for me "
looking at this build I think money's no issue for you (that being said I have no clue how expensive those Royce hubs are).
"Those Royce go for 1.200 pounds per set!"
Ouch! I could safely say: that's waaay too much!
I could see a nice set of Cane Creek Zonos disc wheels (the ones with the Ti spokes) working well on this build.