Leather driving reins
Draft sized harness [also looking for bridle with blinders]
General medical/first aid stuff
6 or 6 1/2 inch bits - snaffles, curb, driving, etc.
Grooming supplies & grooming bags/box
Good set of clippers - doesn't have to be anything fancy, but tough enough to be used on roaching a super thick mane
Will also look at pretty much any draft sized tack you have
I might add to this list later. Thanks!