I'm actually just grabbing at straws to be honest.
I don't know her actual pedigree because she wasn't registered but was bred for sport by a warmblood breeding farm that stood a very nice holsteiner stallion many years back. The mare was named MCR Carlingford. I notice they use the prefix on some of their other horses but since I don't know the farm name I thought maybe they did some race track breeding too.
I am in Canada but she came from the states. The stallion was imported and had the same prefix. She was owned by the same owners. So I dont know the history or if they imported any other horses. But that is unlikely i guess. It will remain a mystery I guess.