This seems to be 2 bits of velcro sown together, would take a few min to make and cost pence but personally I wouln't be keen, lock nuts or seazing wire are much more secure
There is a stainless pin bonded into the velcro wrap. The pin locks the turnbuckle in the normal way and the velcro wrap holds the pin in place. Quite neat. I've seen them in the USA but never for sale here.
I've seen them in the Seasure catalogue, so they are obtainable in the UK.
Personally, I cant see the point, unless you are going to alter you're rigging tension from one race to another. If you are goimg leave the rigging tension alone, then what is up with split (cotter) pins and tape to protect oneself..
I think one point is that you don't have to tape the pins up afterwards. I've suffered one seizure of a screw on a rig due in part to the previous owners over-enthusiasm for taping and the subsequent crud build up inside (and lack of an annual check and clean of course.)
Second point is my shrouds/chain plates are on the toe rail so each time I lift (club uses a mobile crane) I need to slacken the outer wires.