I am very new to knitting, but with the help of my experienced mom last weekend, got a good start on the shorties I'm making for my baby boy! I am using the doodlepants pattern. It calls for 12" size 8 circulars for the legs, but I am having a hard time finding that size and my mom doesn't have the size either. We are thinking of using DPN's? Will that work?

What size of them do I want to use?