I was in the same situation, had a half x he some dog, took everything.
Was planning on studding him to get a pup for myself, then was out lamping one night he callopsed then died by the time we got home. I was gutted.
Sourced a pup from supposedly good stock and the thing jacked after its 5th Charlie.
Luckily got a collie bull grey doing everything I want, I will be taking a pup from her at the end of the season. She is 6 year old now so seen everything I have needed to see.