GSPs can make great retrievers provided water not too cold. Mine are FF, Collar conditioned and trained like a Lab. Just takes longer and skill level usually about 18 months behind a Lab in retrieving if both trained the same way. Not as focussed or mentally as tough as Labs. Our retrieves include blinds 150 meters , multiple marks same distance and combinations of up to three. Channel swims, the lot - just not your distances. All retired guns. They do beat the Labs just not every weekend! Sharon Potter would be a good person to talk to about a suitable pro.