A best bet is the Calvin Klein Men's Topcoat in four colors (Black pictured) for $149.99 via coupon code "CKFRIW". (Big & Tall costs $169.99.) With free shipping, that's $350 off and the lowest total price we could find for such a coat. It comes in sizes 36 to 60 in short to extra long lengths, although not in all combinations.
Of note, in-store shoppers can get Black Friday prices with this printable coupon.