Hi,
Nice find,tracking its origin could be a little tricky though , seals were fairly common in the 17th and 18th c on wine bottles and they usually refer to the owner,not the maker of the bottle ,if it is an owners seal then the other details may help you track it down,coat of arms etc , I don't have a copy but the following book may be helpful and probably available on library loan "Understanding Antique Wine Bottles" by Roger Dumbrell which at the time of publication in 1983 lists all recorded seals from whole bottles and fragments,there may well be an example of this seal in there.
and to answer Sue(M) , they were put on at manufacture , a blob of hot glass on the side of the bottle then the seal impressed , many bottles ended up in the Thames,probably thrown away when broken then over 300 years they get all bust up and the seals become detached and isolated.
cheers ,
Peter.