Wheel building for polo

Clearly you haven't been searching hard enough

http://www.winstanleysbikes.co.uk/product/37483/Halo_Spin_Doctor_Pro_MTB_Front_Hub

http://www.tandems.co.uk/products.php?plid=m11b1s32p177&rs=gb&vid=378

I doesn't it exist for the front, not in 48h.
I've been looking for something similar, it doesn't exist, just getting a custon drilling you can have 48h front hub with disc.
Aswell for the rear, there are no 120mm spaced hubs for disc brake, if your dropouts were 135mm you could get the Halo doctor spin