Something on the retailer

A Link to the Google books search machine showing a journal page with an ad from the company stating

"We guarantee all Guns bearing our new name S.A. Gun Works, late Hillsdon and Hillsdon, to be made in the same Factory in Birmingham as before"

I'm sure you can find more by doing some internet searches

https://books.google.com/books?id=NxlHAAAAYAAJ&pg=PT6&lpg=PT6&dq=