Does the cable itself have anything written on it? "Canare" for example
In the UK at least, Canare used to supply premade XLR, jack and BNC cables, as well as pre-cut lengths of cable and separate connectors, in branded packaging. I haven't seen any for several years - since Canare's distribution changed. All their later pre-made cables over here were fitted with Neutrik NC3_XB XLRs, with earlier examples using Canon/ITT XLRs.
It's some time since I last shopped for cables in the US but CVG (Comprehensive Inc.) used to be a big distributor/retailer of all kinds of audio/computer/AV/etc. stuff. They used to sell Canare cables - both bulk and pre-made - maybe that's what you've got.
(I just had a look online and found
this )