WW2 U.S. 75mm PAK howitzer sight

This is really a very hard to get rare item !!!!!
It is an original sight that was on the British and U.S. used airborne 75 mm PAK howitzer.
Complete with mount and in pretty good condition.
Even the rubber eye pad is still present !
What I could find was “telescope, panoramic,M1” and it is dated 1941.
Further more there is also “Mount Telescope M3A1”.

Markings: mentioned in text
Condition: light used