Well, I looked at the Propstore of London pics, and the compensator says, "ALGIMEC BY LA.RI.A"; I spent the last half hour googling Algimec and the only thing I came up were a lot of legislative type sites and such regarding compensated firearms...
Best bet IMHO, is to PM Wakal or Noeland here; there are alot of gun guys on the board, but those two stand out the most to me...