Moon,
I asked the pros about shovelnose. I considered growing them out commercially. You will never find them for sale.
The shovelnose caviar industry protects their stock with guns. KSU has tried to harvest brood stock and have been chased away by very angy commercial fishermen. There is also the problem of raising them. They cannot find a diet that the fry will thrive on. Best to give up your shovelnose/hackleback quest, Moon.