Kly,
I remember Junket (aka Junket Rennet Custard) from my childhood, some 50+ years ago. It wasn't only a UK product, and until I just did a Google search, I had no idea it was still being manufactured (and by the same company, yet). I certainly haven't seen it in the NYC area in many, many years - unless I don't know where to look.
Check out this Google search results page:
Junket Rennet Custard Now, are you brave enough to order some?

Signor V.