I searched the Pzero by mistake...I'll update this in a few. Here you go, buddy
. I guess they're probably low on stock from the manufacturer...not sure.
Tirerack 275/40R20:
http://www.tirerack.com/tires/tires....FTV2&tab=Sizes
Tirerack 315/35/R20:
http://www.tirerack.com/tires/tires....FTV2&tab=Sizes
TireOptionsOnline 275/40R20:
http://www.tireoptionsonline.com/mm5...=&srch_tbrand=
TireOptionsOnline 315/35R20:
http://www.tireoptionsonline.com/product/955/16866.html