The gun looks very "midlands'ish". It carries almost identical engraving to a gun currently listed at Hill Rod and Gun.
http://www.hillrodandgun.com/picture.php?id=12730
The HIll Rod and Gun example, the action has pins for the cocking limbs, that's about the only difference.
Obviously a Birmingham sourced gun. Doubt it was AA Brown or W&C Scott or even Wrights. The quality isn't there. I would suspect trade gun/action built in house by either Midland, BSA, etc.