There is a Focal-branded lens for which I wish to identify the manufacturer.

I have read that Focal is the Kmart house brand for optical equipment. They also appear to have encoded the manufacturer in the serial number, so in principle, I just need to find a list of applicable manufacturer codes. I have so-far been unable to find any relevant list.

What are the manufacturer codes for lenses that have been rebranded Focal (Kmart)?

This question is a brand-specific variant of https://photo.stackexchange.com/questions/103594  It is written become some think the other question is too broad. If this (and the other brand-specific variants) appear more acceptable, I will make the generic question Vivitar specific.