OK, after checking the AK-74 production sticky...
The sticky claims that "pre-production" AK-74s had a one-piece design and were of the half-moon pattern. Also, the pre-production models supposedly had a "long collar." There is no close-up picture of the pre-production model but there is a profile picture, and it looks similar to the new K-Var model. There is a close-up of the "standardized" half-moon break, and it looks the same as the new K-var part (when it comes to the front/baffle construction area). Only difference being the length of the collar. So I suppose this would be an attempted copy of an AK-74 pre-production half-moon muzzle break. If you were building a 70s vintage AK-74 clone, you could put this MB in a lathe, shorten the collar, and bingo...