cantle, pommle, tree, seat, flap, knee roll, billets
stirrups , horn, seat
pommel
There are over 20 parts to a western saddle. Which 4 do you want to know?
carriage comprises of parts-saddle and apron.
gunpartscorp
Prancer starlight and bell
Part of the saddle, possibly pedals, grips. Parts of the shifters, brake levers.
tree flaps girth straps
A Sybian saddle is a masturbation device for women. It consists of a saddle-like seat containing an electric motor. The woman mounts the saddle and her private parts are stimulate by the strong movement. It can be used with or without attachments that penetrate her.
seat
The main parts are: frame fork wheels (handle)bars saddle seat post cranks pedals
the author's jump over Pecos's saddle
Saddle, saddle pad, martingale, breast collar, girth and stirrups (both attach to the saddle). Leg wraps are optional and are usually just used at shows. Bridle, reins (attached to bridle) and halter.
You can find parts and/or a manual for an Ithaca Model 72 saddle gun in 22WMRF on many gun websites including GunBroker.com and GunPartsCorp.com. You can also find these items online at DiamondGunSmithing.com.