Well Ken Drlong is in MI he may know of some avail pups, Ray Gorman is in Upper NH Coverdog guy also Cooskennel. I saw him recently, I do not know if he has any pups avail.
Those are 2 guys who worked at it over the yrs. Good genetics are imp but you also make a C dog who wins. A different game a bit. Dr Harlings Dogs have done it all in some ways too. NY,