The Australian Jockey

A jockey riding in any race must be at least 15 years old and fully licensed to do so. He may operate independently unless he is an apprentice or he could also be retained by an owner.
Jockey Replacement
An advertised jockey can be replaced by a substitute jockey either before or after the weigh-out, providing there is no unreasonable delay.
Jockey's Dress
The jockeys wear:
Crash Helmet or "Skull Cap";
(compulsory)
shirt and trousers in the owners colours;
spurs;
boots;
Jockeys also carry a whip.
Horse Racing - The Saddle

The saddle is the jockeys responsibility, unless he is an apprentice, which means the trainer is responsible.
The saddle gear consists of:
saddle
girth and surcingle
stirrup irons
leathers or webs
and a number cloth.