For once, I think I might have some useful information to contribute. 1. I vaguely recall seeing that gun in a recent Holt's auction (or similar) and that is I am assuming where you picked it up. 2. Like my Leech and Sons, I suspect that gun was made by G&S Holloway. If so, it will have a short serial number on the bottom rib with an H prefix, this will confirm G&S Holloway origins. 3. If a G&S Holloway, it looks a lot like their model No. 2121 (see image below). 4. If G&S Holloway origins, records are available from Chris Holloway - custodian of the G&S Holloway records: email tipton.harrier@yahoo.co.uk. 5. According to the 1925 Holloway catalog, that model would have retailed for around 44 pounds, which makes it a very nice gun. 6. The Leech records I got on my gun were not accurate, so trust the Holloway records, if applicable.
Here is my post where other folks on here help me run down the origins of my Leech.
https://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=528280&page=1Hope this helps and beautiful gun! Now I wish I had bought it!
Dan