The Walschaerts valve gear is from a Great Western Castle (No. 4081 Warwick Castle) that I built from a Malcolm Mitchell kit (now marketed by Just Like The Real Thing) but the internal parts of the valve gear, the con-rods and the cranked axle, etc., I made up from scratch.
The Stephenson valve gear is from a Great Western Saint (No. 2090 Saint David) that I built from a Slater's kit with many additions, including the internal parts of the valve gear.
The Joy valve gear is from a London North Western 0-6-0 18" Express Goods (commonly called a 'Cauliflower') that I built from a kit, formerly marketed by Modellers World, and with excellent castings for the valve gear supplied by Laurie Griffin and wheels by Alan Harris (AJH).