Case and movement dated L4. Yellow gold plate with yellow case back. Diamonds at 12, 3 and 9. Last photo shows it next to it's white gold / black dial brother.
https://www.mybulova.com/watches/1954-unknown-10409
By process of elimination, I think this may be a 1954 Regent "A". My research is below.
After going through the available price lists, here are my thoughts and observations. In Nov. 1954 under "diamond" in the price list, there was listed the Launcelot and Regent as 17J new models, and neither is in the cumulative list, apparently indicating they are new releases. The first ad I find for Launcelot is dated 1955, and it's a round case watch, so that is probably not a consideration.
In the Nov. 1954 list, there are 2 - Regent models listed for $71.50:
33173 Y - Regent A
33175 W - Regent B
In Jan. 1955 it has disappeared from "Diamonds" and by Aug. 1955, Regent has moved to the cumulative list with 4 models. Based on Price, It appears 2 variants were released after the previous Nov. with solid gold cases based on price
33173 "A", 33175 "B" for $71.50 and
37184 "C" and 37186 "A" both at $195.00
By 1958, all 4 models of Regent are still listed in the cumulative section of the price list.
I have been tracking diamond dial Bulovas online for almost 4 years and purchased the only 2 of these I have ever seen. Both are dated 1954 - one white and one yellow. They came from 2 different sellers located 160 miles apart in Ohio and have very low serial numbers. The white gold previously submitted is s/n 8310528. Subject watch in yellow gold is s/n 8310033. This seems to indicate that they are watches # 528 and # 033. I have yet to find an ad for the Bulova Regent. It's quite possible there aren't any out there.
In 1955, by the price list there were only 6 Beau Brummel models , all apparently of a higher jewel count and 5 are priced $195 - $250, indicating solid gold (?) . I would rule them out. The other is most likely the 17J "Squadron case" model .
All factors considered, it's my opinion we are looking at the Bulova Regent. Never advertised and released to limited markets and a short lived marketing/sales flop.
Thoughts?
You certainly present a compelling case Bob. As you know, I'm always the 'but show me an advert guy". The serial number and seller proximity is curious but .....gosh, it just doesn't support an ID. The watches are clearly related and are wonderful examples of 1950's styling. I would wear either one but am particularly partial to the white gold/black dial model. Alas -
1954 Bulova Unknown (sorry)