There were women's White 'Whitaker' jodhs up on sports direct for 30-40€ couple of months ago! If they are still up on the site I recommend them!
SmartPaks Pipers and Equine Cotures are cheap
I personally like Devon Aires for cheep nice breeches
I have white full seat Piper's for show jumping
I have a couple pairs of Piper breeches. You can normally find them at a pretty good price rather you want full seat or just knee patch