I guess you know it's a British-version Victory made as a Lend-lease gun for Great Britain, about 1942/43. You'll get a better date here soon, I think.
This is a really nice one. There are a lot of the British ones out there, having been re-imported post-war, and they are generally in crappy condition, have been modified, refinished, had their barrel shortened or cylinder bored out, and at least have been decorated after the war with British proof marks and/or importer stamps. As a result, most are not very collectible.
From what I can see in the photos, yours does not appear to have suffered any of that. Nice find! I'd pay as much for that one as for the US version.