I believe to be the first of this variant for the DB. 1963 Bulova Regatta 23 "E" based on the 1964 Linebook. Yellow gold plated case with stainless back. M3 date code. The dial is a gold color with yellow gold applied hour markers at 3, 6, 9, 12 and faceted squares at the other positions. The movement is a 23J 10BZAC. Going to dig thru my pile of bracelets to see if I have a close match to the one in the linebook.
I wonder the differences between the 'E' and 'F' variants - besides the band:
The shading on the dials are not quite the same. Could one be gold vs silver?
In reply to I wonder the differences… by Andersok
Ken - are these both from the same linebook? Which one, which page?
In reply to Ken - are these both from… by Geoff Baker
Geoff, they are both on the 1963 linebook, page 35. So different variant based on band it looks like.
If it is the band, then it will make this ID a little tricky.
Above linebook reference is 1963_LineBook_BAWD0151.pdf
The band is the 'variant' and not the first time We have seen this.
'REGATTA 23'
1963 Bulova Regatta 23 (generic based on the 1963 linebook the "E" or "F" is based on the band it looks like)

Suggest we leave the variant off this one. 1963 Bulova Regatta 23