Cutting a spinner is not that hard to do. Go down to the local hardware store and get a bolt and nut combination thre diameter of the prop shaft long enough to secure the prop to the back plate. If you want to get really fancy, make the bolt long enough aand with the same thread as the prop adaptor nut so you can perfectly but lightly calmp the spinner over the prop. Use a magic marker to make the initial cut outlines, while being somewhat conservative. Use a small grinding wheel to make the initial cuts, but be careful not to try and take too much, too fast. A Dremel is NOT a good tool for the job. Re-install the spinner over the prop and make new guide marls for the final cutting. Use the grinder for the big stuff and a file used for sharpening chain saws for the fine stuff. Try not to make any sharp points at the base of the spinner, they always blow out under rpm loads. Polish to taste and go fly.

One easy evening will do the job.