I had to log in so I don't know if this link will work. Is the owner of this gun here? Timothy S how does this compare with your gun?
http://www.jamesdjulia.com/auctions/catalog_detail_shots.asp?Details=30220&sale=209SCARCE HIGH GRADE THOMAS KILBY DAMASCUS DOUBLE BARREL SHOTGUN. Cal. 12 ga. SN 1062. Fine English made double with 29” fine Damascus bbls choked IMP-MOD/IMP-CYL with tapered, concave matted rib, sgl bead, crossbolt rib extension, dbl underbites, ejectors & dbl triggers. Maker’s name is on rib. Mounted with highly figured English walnut with full checkered & leaf-carved splinter forearm with Prince of Wales stock, 14-1/4” over a carved & serrated horn buttplate. Stock has deep foliate-carved teardrop side panels and extensively carved foliate & floral wrist with stippled background. Bottom of grip has a black oval insert and there is a blank silver initial oval on bottom of stock. Receiver is elaborately engraved with the vignette of a bird dog on point with two pheasants on left side, a setter with two ducks on right side, a flying crane on bottom and a running doe deer on trigger bow, all surrounded by full coverage, very fine, foliate arabesque patterns with fine borders and a sunburst around hinge pin and the maker’s name is on each side. Appended metal is all engraved to match. Fences have side clips and it has, over the entire top of receiver, very deep relief, floral & arabesque engraving. Top tang has “SAFE” in gold. Accompanied by a pair of 28 ga. Briley sub-caliber tubes with screw chokes, having a total of four chokes. Also accompanying is the Briley hammer & removal plug. Additionally accompanying is a green felt-lined, leather case. Bore diameter: left - .725, right - .726. Bore restrictions: left - .025, right - .004. Wall thickness: left - .022, right - .024. Drop at heel: 2-5/8”, drop at comb: 1-9/16”. Weight with tubes: 7 lbs. 3.84 oz., weight without tubes: 6 lbs. 5.12 oz.. CONDITION: Bbls retain most of their orig strong Damascus pattern, slightly thinned over forearm area. Receiver retains 60-70% orig case colors, strong & bright in sheltered areas, fading to silver elsewhere. Triggerguard is silvered case colors. Wood is sound with minor handling & storage nicks and retains about all of a fine professional restoration. Mechanics are fine, bright shiny bores with light pitting just in front of chambers, may have been honed. Case shows light to moderate wear with some light water staining on one end. Interior is slightly moth eaten. 4-30220 JR64 (5,000-7,000)