Below are some excellent resources for finding equipment.
Horse Bows - Our man is Atilla who was born in Hungary, but lives and works here in the USA: traditional bows and archery equipment of Turkey, Mongolia, the Magyar people, and other horse archers of the steppes.
More Horse Bows and Helmets - Grozer does great work and is reliable.
Arrow and Helmet Resource - Seven Meadows Archery is where I got my arrows from.
Boots - This is a decent source for nomadic horsemen boots.
- Most boots are about 69-74 dollars. Go for the ones that
are solid black or brown colors and have treads on them for
traction (that last point is important since you don't want
to slip one way while asking your body to go another) (this
Fiberglas Spear cores - From McMaster-Carr. These are the best cores for spears available.
Fur/Horsetails - From Moscow Hide and Fur