Welcome to the forum.

A couple of books you may be interested in getting;

"Shooting the British Double Rifle" by Graeme Wright

and

"The Hammerless Double Rifle" by Alexander Gray

They have nothing to do with Taylor but thought if you were interested in Double Rifles they would be right up your alley. Wrights book is the better of the two in my opinion but Gray's book is also good (although don't spend too much on it as there are some people who think it is worth its weight in gold).

Also highly recommend you getting "African Rifles and Cartridges" by Taylor if you dont already have it. Some very good info.