I come from the background where these pickles and many other things were passed down as family heirloom. It appears one of the china jars we used to store the pickle (raw mango) was from 1800s and one was from Spain.
My family primarily did mango pickles and the oldest one I consumed was around 20 years old. There were 100s of varieties of mangoes each very distinct but around 4 specifically bred of pickle. We used fenugreek and coconut oil as some of the ingredients. Each year we made pickle of around 100 tiny raw mangoes and stored for future and passed on some old pickle to the friends and relatives (never sold it).
I do not think in my region this was a big deal, most of the classic and wide variety of pickle seems to come from Rajasthan.
Few other food items that were passed down over generations:
1. A bottle of alcohol. (Only used for medicinal purposes) this was around 200 years old and purchased from a sailor from Portugal. It was an extremely powerful Cashew fruit distilled alchohol.
2. A very weird kind of gourd. This was fucking far too old. I mean older than my great grandmother and which she brought as dowry from her mother or something like that. I do no even know why and how it was preserved but it supposedly had some medicinal properties and people often came to my grandmother with offers to buy it. Eventually someone stole it.