Trigger's Tack.

NPC Location: West of Pony Express.
Level: Advanced. 
Quest Points: 300.
Items Required: Magnifying Glass, Binoculars.
Reward: $7000.
Notes: Saddle Pad: Talk to Waverly and go north to Blowhole Forest. Back to Trigger.

Bridle: Go to Wington. Talk to Iris, and Daf has it. Return to Trigger.
Saddle: Get his saddle from below the Willow tree on Hoof. Return to Trigger.