Help dating this jacket?

[Dinerman]

I picked this up today for a couple bucks at the thrift shop. It was the fabric that drew me to it. Very heavy weight wool, in a midnight blue, almost black herringbone. Fully Lined with striped lining in the arms. No tags anywhere; I checked all the pockets, and checked for any markings on the insides of the arms.
Surgeons cuffs. Vented back. Curved ****** pocket.

I'll get some pictures of it over the weekend when I'm in the sun and not standing awkwardly for a self timer.

 

[Guttersnipe]

WOW that is a tough one to date

In the absence of union tags I usually go by details like, the type of lining, finishing work, back vent or not, material, hand sewn finishing, etc.

The detail like doctor's cuffs, stout material, and lack back vent, are definitely signs of a very old jacket. The full lining throws me off; usually when I find older suits though, the jackets aren't fully lined.

 

[thunderw21]

Looks '20 to me, possibly earlier. The button stance is different (high, rather close together).