While Knoll still sells Jens Risom's Lounge chair, one of the very first designs produced for the company, Design Within Reach (DWR) exclusively offers the Jens armchair and ottoman. They are based on designs Risom originally produced for the Caribe Hilton Hotel in Puerto Rico in 1949. Though they still look the same, DWR have collaborated with the designer to update the production techniques, meaning you get mid-century style married with contemporary cost-effectiveness.
Sadly, this is a treat for North American readers only as the company doesn't offer international shipping. If you do reside that side of the Atlantic, the chair is currently reduced in their sale to $935.
See it online