Figured since I was having problems finding lug nuts that fit the skinny lug holes people could post Brand of lugs/size and any links etc that they have used with there XXR 521's to help people in the future =)

Lug nut brand/type:
Size: 12x1.25 and lugnut size 20mm x 34mm etc
Link:
Pic installed:

 

The project kics r26, r40 are 17mm x 26, 40 (respectively)

 

I ordered a set of the Project Kics r40 after calling 2 places and they confirmed they fit.

Will post pics when installed in this thread for future reference for others =)