I have never been lucky enough to be able to purchase live scallops in the shell. It's illegal in most places in the USA to even bring them in on the boats that way because they are so perishable once out of the sea. I keep live oysters, clams or mussels in the fridge for a few days, but that seems not to be the advice for scallops.
- "How to tell if a scallop is still alive…
- Live scallops will have their shell at least slightly opened. They should close at least slightly when pinched or tapped on the counter. Scallops really should be cleaned as soon as possible, as opposed to keeping them alive until just before you cook them. If you must keep them in the shell for a day, put them on a tray in your refrigerator and cover them with a damp cloth."
Above quote is from the SaltChef website here.
There is also information on this website on storing live scallops in the shell.
If you do wind up shucking and freezing them, that reddish-orange stuff in there (if any) is roe, and should be either frozen (I have no idea if it freezes well) or what I would do is cook it up fresh in butter for cook's treat and freeze the abductor muscles for your dinner on Saturday.
If you do not mind saying, @Dennis1404, where are you that you can mail order this delicacy, and where can others of us get some?