Just Added An Inland M1 To My Collection But Have A Few Questions

[Albayo]

I have an Inland M1 with a serial number 1182XX. Its a nice little gun but I presume has been reissued post war to L.P.W. as marked on the recoil plate. Its trigger guard is marked WB-LP-0203.
I don't really know what these organizations are?

[Tuna]

Post WW2, carbines were issued to a number of different Police and border guard units in German and Austria. The markings you ask about are from units in German that had carbines. Many are now mixed onto other carbines because of rebuilding in German. But the parts you have mean they were on a Bavarian carbine. It may have been imported by the likes of Century Arms or could even have been CMP who had it. But many over the years have returned from Germany and Austria.