Nonnative has a cool looking one this season. Though doesn't look quite as long as you are looking for. They probably have done something similar in past seasons, so you could also try searching used on yja or grailed or whatever.
Stephan Schneider quilted sweater. This is from FW14, really nice easy-to-wear piece. This is new with tags.
Tagged size 6. This fits well for a large, or could be relaxed on a medium.
$125 shipped to CONUS (paypal included). PM me for quote to ship elsewhere.
Geller fisherman sweater from FW15. New with tags. Really nice slouchy sweater. Great beige (called mauve) color and nice knit pattern. Fits a relaxed medium or large. Long in the body and sleeves, would work really well on a tall medium.
$225 shipped to CONUS (paypal included). PM for shipping elsewhere.