Seikanon lenses????

According to a forum post I found, they were a chain store 'house brand' at one point, so I'd assume like other stores, they were contracted out to whomever could produce them with a reasonable margin left for the chain when sold. They could actually be a mish-mash of different brands and will take some detective work to find who the maker really was for each individual model.

I don't know if there's a direct comparison with how department store brands work outside the US, but at least for those I'm familiar with in the States, the mounts could change just as easily as the manufacturer of the underlying item brand.

KMart (the mall and super store version of S. S. Kresge's 'Five and Dime' stores) had a revolving door with no allegiance to stock the same mount for any consecutive year or even within the same year, and given the nature of the parent company, it was surely about whatever produced the best profit margins and they never put the quality of the product at the forefront. That's not to say that they didn't occasionally manage to sell some better than average items... it just was a coincidence that they had them at all.

Sears Roebuck and Montgomery Ward were a bit more upscale and valued the quality enough to get better products, but they both still weren't very conscious about what switching lens mount meant to customers. They were heavy competitors and both were big on very large scale catalog merchandising for sale presentations and even special sales (equal to today's 'black friday', if you will) and they were nationwide. KMart started out more regional to the upper midwest, and weren't into catalogs or competing with the 'big boys'.

Most of us on the forum might be familiar with the Tower brand from Sears for the Nicca stuff from their final years, and later on, the plain-jane Sears line that sold the Tomioka 55mm's on T.L.S. cameras in M42. Which reminds me I've got some photo shooting to do on that front)

J.C. Penny was the other part of the Big 3 of the day, and they were somewhere in between the others for prices, and pretty much in the same league as KMart on mounts and manufacturers, but they tended to have less turnover in what they offered year after year.

I'm sure there were other retail chains in the US at a more regional level that I'm not familiar with, but I can say that it wasn't the same with retail camera store chains. I don't think I've run across any other house brands that might qualify, but there might be something in low volume that doesn't show up often.

We didn't really have to much in the way of national camera stores either, and the only ones I know of that might have had 'house brands' would have been Ritz Camera. They have changed a lot since they were bought out in 2012-ish, and I don't know what type of branding they might have had. I wasn't a frequent buyer to know their lines.