Check out individual PC websites - our members only tend to post on our one. We find Horsequest to be a great place for better quality animals. We put one of ours on there yesterday but sadly, for you, only 122!
PC website here as well. Horse and Hound classifieds. Wherabouts are you? We have an excellent (but not cheap) dealer near to us, and also have bought from a dealer near Stratford on Avon, who I'd buy from again