For those doing a K style stealth costume (one with plausible deniability), I can recommend
Baracuta oilskin outerwear in forest green. I ordered a G10 winter coat on sale as an impulse purchase, and was determined to return it once I received it after much recrimination. However, the weight, color, and movement of the waxed cotton is dead-on to my eye. The color is liminal, at once black or dark gray and green. The navy blue coat looks cool, too, though I've not seen it in person.
The shape has a slight A-line from the shoulder to hem. If I measured correctly, mine (US/UK 36) is 32" from shoulder to hem. At 5' 7" or 5' 8", the hem falls 3-4" above the top of my knee, about the same length as K's "action coat" (below) that we are not supposed to notice. It fits true to size and appears to be very high quality. Baracuta has a long history from Elvis to Sinatra, Steve McQueen, Tom Cruise, etc. Their most famous jacket is the G9, but this G10 makes a pretty great Blade Runner-ish jacket if you are interested in Blade Runner-ish style over verisimilitude.
I might put some patches on it or maybe add some detachable sherpa. K's actual coat looks to be more of a Belstaff style (from the felled shoulder detail), but this Baracuta one is a fine detective coat, too. They are having a sale at the moment, 40% off. The color of this really makes me want to run through a wall at full speed. The waxed fabric is a bit stiff in a good way--it has some memory. I expect it to develop unique wrinkles and wear similar to a leather jacket or a pair of good jeans.
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