Well, I have the twin to that gun. 30" damascus 20 SLNE, SN 14649. My gun was made 11/18/1895. You did not post your SN. Are we close? Please use my SN as a reference for dating your gun.
I have the 430 West Strand London on my rib. My label is 62 South Castle St. Liverpool, but otherwise it looks like your label. The gun has a 1 on the barrel flats that would make you think it was part of a pair. Alas, the 1 appears nowhere else on the gun. I would like to think it may have started as part of a pair that just never happened.
My gun has the same pre-1896 proofs (21/20) and a more recent London reproof to 70mm in 2002.
T Bland & Son is now owned in the US, by Col. Glenn O. Baker in Pa.
He can provide you with a letter about your gun for a modest fee. His website is
www.woodcockhill.com. I used the website to get my letter. Glenn was very prompt in getting my letter to me.
Joe
I will post my pics in the morning.