My retired E8 friend carried a combat knife that looks like an M-16 bayonet with a different guard/quillon, and a plain pommel without a latch.
He said that he bought it before being deployed for Desert Storm. It has a tan handle and sheath. He said that some outfit made them up, but the military didn't buy them for issue, so they were sold to the public. I've seen them on eBay and pictures of them come up if you search for "desert storm knife combat tan m3 m10".
