I have a similar Tolley with 30" Damascus barrels. Mine is in less than perfect condition because the stock has been over sanded near the receiver and only one ejector functioned sporadically so after spending $300 to repair them I decided that it was fine as an extractor gun so I had the ejector springs removed. I kept the springs should a future owner wish to spend more money than me to fix them I have about $1000 total in the gun and shoot it occasionally, including last Saturday.
This gun also has the "Westley Richards" type cam top lever but, in addition to being narrower, their is no "slide" visible when the top lever is pushed to the right so the design is somewhat different. It does have an Anson & Deeley patent use number. The ejectors are "J. Dallaways Patent Ejectors". I spoke with Westley Richards and they told me that they have no records on guns sold in the white so there is no way to know if they build it.
My serial number is 68XX and dates between 1887 and 1894; it's marked "choke" which began in 1887 and the rib is engraved "1 Conduit St - Regent St London" an address they left about 1894. The gun is Birmingham proofed so there is no doubt that it was Birmingham made.
The 9100 on your gun is the serial number.
