Sunspot will be the way to go, not sure what other heads you could use that may still fit on the peg and look good in alt mode. I know you want to limit the modding as much as possible, but perhaps a little putty to civer the front of the face and allow you to paint eyes on would be a small enough job?

My local Woolies was selling off HftD basics for $10 if you need one. lmk.