Odd Winchester Model 12 Trench Gun|Winchester Military Arms|Forum|Winchester Collector

I have an interesting 1948 Winchester model 12 trench gun.  The gun is in near mint condition and the serial numbers match.  The gun has the flaming bomb on the top of the barrel but is mat marked U.S. on the receiver.  There is a 3 letter cartouche on the stock but is small and hard to read.  Any Ideas? Thanks

matching and in near mint condition.  It has a flaming Bomb on the barrel but is not marked U.S. on the receiver.  It has a 3 letter cartouche on the stock.  But is very hard to read.  It could be BPA or VIU?  any ideas about this gun?