I have tried in vane to find a serial number, alas can not find it. I have also attempted to research this model but have not found one with black keys, like this one. My research gives me 1941 as its date and that it is one of the last in its production run.
Since it is an American typewriter and comes from an English source at the beginning of WW2 it is very special.
I AM OUT OF MY COMFORT ZONE HELP WITH ITS PEDIGREE APPRECIATED
The typewriter appears to be in extremely good condition though might need lightest service
The previous owner has glued the front fold down panel of the box easy restored

I post to all countries. On posting day I will send tracking details.
Check out my feedback for quality assurance.
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BOX
ROOM