If you need to ask, then you're probably not likely to speak Canto or venture into Chinatown without a guide?
So I'd say T&T.
I've never bought it there,
but I think it's sitting pretty near to the preserved pork belly, cured duck and lap cheong sausages.
Handy tip,
If you ask in English, and they can't answer you, then they are probably literate in Chinese.
Just show them this and ask them where?
https://en.wikipedia.org/wiki/Cantonese_salted_fish