Think barter. By 'gold-backs' I presume you mean official currency; barter is an unofficial transaction, the govt needs to know nothing about it.
As to where to store gold and still have access to it, that requires some creative thinking I suppose. If you buy gold on line and/or by credit card I would think that the govt would have a record of it. I have seen hollow artificial rocks that would blend with your landscape. Stories are common of people who buy an old house and in the attic or chimney or basement they find a hoard of silver or gold coins that a previous owner hid and subsequently died.
Presumably professional searchers would use metal detectors. Forget safety deposit boxes; already the govt is seizing them without even a warrant.
There are many common items good for barter - like aspirin, for example. CoViD proved the value of the best known barter item: toilet paper. Study barter on survivalist web sites and consider what you think your neighbors might most likely need to trade for.
In deflation everything of real worth loses value: real estate, autos, tools, precious metals -- but there is still a need for such things. Use your imagination. 😉 😇
I had a "good ol boy" tell me about his grandpa. He had a bunch of old pipes strewn about his yard. When, as a kid, he was fooling around with them, grandpa opened one up and it was filled with quarters. After grandpa died someone who didn't know the story had those old pipes hauled away.
It's a regular thing for PR to trade in silver. We have used small denomination (.10 oz) gold coins to make private purchases locally. We are supplied with fresh eggs, Moose meat, fish etc. in exchange for services PR provides or other "Valuable considerations".
Of course, under the table purchases at small businesses with hard money would be illegal so that never happens.