Speed Shop in Florida is willing to make some catless DP's for X5M's\X6M's for $680. I live in Cali but he asked if I could find someone in Florida that would be willing to lend him their car so he can fabricate the DP's. I am sure he would either give you a set for free or at a reduced price.
The Shop is DG Autowerks
this is their instagram:
https://www.instagram.com/dgautowerks/
you can see his work, and if you are willing, DM him on instagram about the DP's.
I think once someone charges less for S63 DP's the other company's will fallow and reduce the price of theirs as well.