As for price. It all depends on what you you'd like me to make. If I made a plush with this kitsune design I honestly wouldn't know what to ask for them yet. I have no pattern, no colour, no plush prototype. I need those first before I can decide on a price.
And I say patch because you'd be able to capture this drawing in as many different colors as you wanted. A plushie would also be cute! But I imagen the beads would be some trouble to make/find depending on the plushie size. If done though, I have no doubt that he/she would make a huge success if placed up for bids.
I know right?! Ive only made simple plushies up till now. I hope you know just how talented you are! You could always make one big one as a mascot or something (an excuse to keep it) and on occasion to small magnet ones in custom colors and such, along side patches. I know Id buy a patch. No idea what id put it on thoug. xD