"we must have the obligatory tin of processed peas that finds its way into every jumble sale and onto every tombola stall and has, at one time or another, been through the hands of every person in the village. Woe betide anyone who dare open it."

I reckon *that's* your village memory stone right there. Probably got the genetic fingerprints of every resident of the village going way back to err the dawn of villages. After the apocalyse, millenia will pass, then alien races far advanced of us lot (and via amazing future science methods) will find said can of peas and unlock the entire history of our wee village... They'll probably get it about as botched as WaV's own idea/ls. So when they clone us all and pop us in their re-imagined aliens cultures history zoo, it'll be just like it. Mead & chips and all.