Another 'What is this from' thread. Gun sight mounting bracket

As the title suggests.
Can anyone help with the identification of this bracket. It would appear to be a gunsight mounting bracket but I have no idea what from
I was originally thinking Typhoon/ Tempest as the guy I got it off collected parts from those 2 types.

It has the numbers 10346 then a smaller number 9 and then a number 3 by itself
It has has some other number on the circular lip but these are partially missing. They were something like C9D6 ? and then another set of 6 ending in 250

Many thanks for taking the time to look