Check the SWL http://www.wichard.com/rubrique-Chain_grips-0202040803000000-IM.html
On my anchor bridle I use one of these instead, in the largest size, with a spliced Dyneema loop tied around the rode in a Prussic configuration. It's two steps instead of one, but each step can be done with one hand.
http://www.wichard.com/rubrique-Carbine_hooks-0202040500000000-IM.html