First, making the pumpkin seed flour is not as simple as it sounds. There's a lot of factors they may become a problem to consider when blitzing nuts or seeds. An good example is the natural oils in the nuts or seeds itself may cause the mixture to clump up into a semi paste if your blade is generating too much heat from spinning. So you might have to think about doing this in a 2 step or 3 step process, giving time to allow the nuts to cool down and dry off a bit before continuing to blitz the nuts into a finer consistency.
Luckily, my kitchen aid hand blender comes with 10 speeds. The blender is a roaring beast. But even at it's highest speed, it is unable to slice the seeds into a finer, flour-like consistency.