I am not big on the relics, I took these with me, the harness piece is broken on one corner. They may be old, I detected a old ox shoe in the same exact area last year.
the horse bit is a nice find, I have yet to dig one of those. The horseshoe also looks like it's been in the ground quite a while, though not sure on the age.
Maybe 1870-1900 on the horse bit? Hard to tell without really looking it over closely for the construction methods.