From third hand information, I gather that these are the Creata/Winner's Choice molds sculpted by Candace Liddy. Circa 1999, Creata stopped producing them (in the middle of "series III"). There apparently was a copyright violation by a company called "Toob". Breyer bought the line (through Candace, bankruptcy?) and began producing them in 2005.
San Moritz Winter Festival Play Set (#300105)
Released 2005. Photo taken at outdoor venue.
Irish Countryside Play Set (#300106)
Released 2005. Photo taken at outdoor venue.
Australian Outback Adventure Play Set (#300107)
Released 2005. Photo taken at outdoor venue.
Day at the Races Play Set (#300133)
Released 2006. Photo taken at outdoor venue.
Goose Creek Stables Play Set (#300131)
Released 2006, part of the Flicka promotional sets. Photo taken at outdoor venue.
Canadian Rockies Show Jumping Derby (#300126)
Released 2007. Image taken at BreyerWest 2007.
Adventure Vehicle & Two Horse Trailer
Released 2007. Image taken at BreyerWest 2007.
Lone Star Cloverleaf Challenge Play Set (#300127)
Released 2007. Image taken at BreyerWest 2007.
Silver City Hacienda Play Set (#300124)
Released 2007. Image taken at BreyerWest 2007.
Sunshine State Dressage Festival Play Set (#300125)
Released 2007. Image taken at BreyerWest 2007.