Wow! Your geese are absolutely perfect! They don't even have leakage, which is a hard thing to not have with the Sebs. No angel wing either! I definitely would sell the goslings for $100 a gosling, $75 minimum. Those birds are valuable, and if you sell them for anything less, you're literally...
:welcome:welcome:welcome
Welcome to BackYard Chickens from here in Maine! For a quality Sebastopol gosling, you could probably sell it anywhere from $50-$100 a gosling. If you're hatching them under a goose, I suggest waiting until they're older before separating them from the gaggle to sell.