The Remington Hammerless Doubles last appear in the 64 page 1909 Remington Arms Co. catalog. Here are the pages 18 and 19 with the Trap Guns --
1909 Catalog pg 18 Trap Guns pictures.jpg
1909 Catalog pg 19 Trap Guns text.jpg
For most of its years the CEO-Grade Trap Gun listed at $95 but got a big price increase in this last catalog.
The Gun Behind the Man, The American Field, Mar. 2, 1907.jpg
There was also a 36 page 1909 Remington Arms Co. catalog that didn't include the doubles.
The highest serial number Remington Hammerless Doubles I've recorded are a nest of D Quality guns with Krupp Steel barrels that I guess we would call DEK-Grades in the 1406xx serial number block. A few years back Steve Barnett had 140674 for sale. I looked at it at the winter Las Vegas show.
140674 01 REMINGTON-1894-DEK-SXS-12-GAUGE.jpg
Serial number 140670 28-inch straight grip and 140672 30-inch straight grip sold at the December 2019 RIA auction. I've also seen 140667 a set of Krupp barrels. Wonder if they will appear as a complete gun one of these days!!