I've tried to use different types of corn flour, but it's never quite right. The nixtamilization process dramatically changes the texture of the resulting masa. Fresh masa is even better, and can be made yourself if you're up for a project day.
I agree that flour tortillas may be your best bet if you can't find maseca. A wine or round liquor bottle with the label removed makes a great impromptu rolling pin.
Even better than (or in combination with) a rolling pin: Squash your dough ball with a flat-bottomed pot or pan. Easier with plastic on either side of the dough.. I cut open a gallon storage bag.