Hi there,
I loaded it into photoshop, which can handle resizing better than most programs. I made two versions for you, since I thought you might like the palette to be covered up in your avatar and it was an easy enough thing to do ^^
I hope one of these helps!!
Edit: I just realized that the one you attached here looks a lot lighter than the one I pulled out of your oekaki gallery, I can redo it with the lighter one if you'd like later.