New belts can be found a local sewing centers , but you will need to meaure and cut and staple yours. It will need to be a bit loser than you might expect. I am not good enough at this to give you directionsl There is a way cool pair or pliers for cutting the belt and for punching a hole through it for the staple, but it can done with a knife and and ice pick or an awl. You may know already that this is called a fiddle base. looking good.
assuming you know that the hand wheel runs anti clockwise. I often stitch with a machine before I hand a belt on, just my turning the wheel