https://www.ebay.co.uk/itm/Glasgow-H...p2047675.l2557
Glasgow High School but not the OTC badge I am afraid.
The fixings are not right for a cap badge. The school wore a round badge in brass with the school OTC title before adopting the white metal Cameronian's mullet badge.
The round OTC badge can be found both solid and pierced. When they adopted the Cameronian Rifles' badge they continued to wear the round badge on their sporrans.