That's the company "Gaskets for Classics" who remanufacture gaskets for all classic cars.
I believe they have a good reputation.
I've not needed to use Gaskets for Classics yet, 'cos of my own spares supply, but I'd go for one of these brand new sets any day. I've bought apparent NOS items before and found that the reason they've been stood on a shelf for so long, is a couple of items have been pilfered over the years and the set is no longer complete.
Bri.