I purchased four chairs from a vintage store. They have a France & Son tag. I searched the Design Museum furniture index and they appear most similar to an armchair model 196 by Finn Juhl. This chair appeared in Mobilia no. 87 (1962) and is dated in 1961. The original upholstery was leather; these have been done in orange vinyl. Have I identified the chairs accurately? If so, would anyone have an idea of what color the original leather upholstery might have been? Thank you. 
The chairs are
originally upholstered in black plastic / vinyl and have 2 different back sizes.
The smaller back chair was for ladies with the slant of the armrest being horizontal where as HIS chair had the armrests slanting forward.
here is a pair of the chairs with the original upholstery.
. . .
Thanks very much, onno and Simon for sharing your knowledge about the additional background. I have a Nils Johnsson Swedish teak buffet, table and chairs and was looking for something to blend. Wasn't aware of what I had acquired until after I purchased it. It has been suggested by someone familiar with mid-century design that they might have been done as part of the Diplomat series. Do you know anything else about the chairs?
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