The Barrhead Goose is commonly found at altitudes of 30-50,000ft and have been responsible for a few strikes of airliners at high altitudes.
I have had one strike at Orkney with some kind of marine gull (to me it was a seagull but from a previous post I now realise that there is no such thing). Was in the take of roll and a flock of marine gulls flew in front of me, most of them scattered but one (maybe (s)he he didn't see the rotating prop) flew straight through the prop and glanced off the wind shield leaving a smear of blood on the perspex.
Stopped on runway and taxied back, the gull was perfectly sliced in two diagonally across its body, no blood, guts or feathers scattered about. His mates were circling above ready to take advantage of a free meal. I removed the parts from the runway so denying the circling masses of their dinner.
As previous a poster said and from my experience, think it would be difficult for a bird to go straight through the windshield in a SEP as the prop gives you protection and will scatter and disipate any energy between the bird and the windshield.