Sight question/new carbine

[painter777]

WRA Oblong cut out:




Markings:



NOTE:
Very early Type I WRA housings were found stamped with just a O

But I believe these were very few.
Look for any numbers and or letters stamped on the outside bottom of the housing.

Like this:



Serif K Under Right Side Shelf of Trigger Housing:



Side view of a WRA Type II- Rear beveled corners, No bevel front, Wide wall: