Richard,
I'm in Crete and we don't have antique shops here. In fact, very little second hand at all - people tend to run things into the ground! The boxes of 78s weight a fair old bit and there are fives boxes of them. My car was 15 years old when I sold it, and that was a relative youngster here. Our original idea was to convert all this old stuff into digital and I have the equipment to do it, but it is so time consuming. But now CDs are on their way out and CDs that are burned on a computer only have on average a life of 5 years. Commercially pressed stuff lasts a lot longer, but soon you won't be able to get anything to play them on anyway. Member sticks last somewhat longer, but that is the ever present problem of people involved in archiving - the ever-evolving different formats.
Some years ago I was contacted by a museum because I was one of the few people who had a working copy of a DOS database called GIM (Genealogical Information Manager). They'd been left a family tree as a GIM file and had no means of reading it, so they put an ad in Family Tree Magazine and I was the only person that responded.
Maurice