It’s cause he’s out of country fyi
I would love some 18x10.5 as well… and i wish i’d get them widened some! That would be bad ass! 18x11 rpf1s up front and 18x12.5 rears… 
Some guy did it on his fd rx7 it was posted on zilvia… i can’t remember if he widened the rears to 13" or what… it was bad ass looking though