Hellis was in London. The guns I have seen/owned were sourced in Birmingham from Webley & Scott. Pre-WW2 boxlocks had Greener style 3rd fastners, my ca 1950 post war gun doesn't have the 3rd fastner. I found it on a rack next to some W&S 700s. They were the same except for the engraving and name on the barrels. The sideplated Hellis was $2000 less with than a "real" Webley BLE.
I'd buy another if it came my way.
Hellis was a large retailer of 2" 12s. I got a chance to handle one in the UK recently. It was really nice.
I have been watching for a 12 SLE. The top grade guns are beautifully engraved. The lower grade guns are good values IMHO.
The company still exists http://www.hellis.com/

Joe