Hi Mark. There are several variants from around that period. When Dad joined in 1964, he was issued with a flat, chrome-on-brass badge(which he still has), but there are also thicker cast copper(alloy?)badges too, some marked Gladman & Norman. (See
HERE.
Some have the apostrophe after Owners(') some don't. Some have a 'strengthening post' where the Gladman text is on others.
I hope you can see some of
MY PHOTOS here, and compare the ones I have mentioned to the others on page this page.
I'm away with work but can give more info when home on Friday.