Wonderful find, mate!
I wear the Regulation Doublet for most evening functions, yet it is a 'modern,' bespoke version made by Kinloch-Anderson. No worries on your lovely doublet not coming with a matching waistcoat, you can easily have a bespoke tartan (on the bias, or not) or solid coloured waistcoat (I sometimes wear one in scarlet) made that will look quite smart for evening wear.
I agree with you and Sandy; I too prefer the look of the 'Inverness flaps' coming all the way to the edge of the front-opening of the doublet - a much smarter look in my opinion - versus how they are commonly seen today. This gives the doublet a nice 'vintage' feel to it. I also like how the three buttons on the front are not in the typical diagonal placement.
Me in my Regulation Doublet from Kinloch-Anderson.
Meyer & Mortimer...I'm impressed..well done!
Cheers,
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