This is Wonder Woman from Mego's Comic Action Heroes line of 1976. The strangely masculine head on the left was quickly replaced by the one on the right. The unfortunate body style remained unchanged. You can purchase the original mint-in-packaging for around $150 to $200 on eBay. (via SuperPunch)
David Pescovitz is Boing Boing's co-editor/managing partner. He's also a research director at Institute for the Future. On Instagram, he's @pesco.