Does anyone recognise this old Mathey-Tissot chronograph? I'm interested in manufacturing year, movement maker and caliber (Lemania 13CH29?) and in what branch of service it may have been used? All I know is that it says 12995 under the balance and Mathey-Tissot on the bridge. The width of the movement is 29mm. I attach some pics to better describe the item visually.

I originally posted this in an other forum but was recommended to post it here instead.

Thank you for your time!