I visited Tintagel a few months back and walked past a house where I thought there was a gift shop once. Not sure if I was imagining it. I'm sure I went in there in the mid-90s and there was a young lady working in there with a black cat, then visited again sometime around 2003 I think and there was an older lady working in there... and that black cat was still there I seem to remember. Not sure if I'm imagining it though. I wasn't imagining the people but sure the location was was right next door to the toy museum.
Originally the toy Museum and the Gift shop you refer to was a lovely old cottage. The Toy Museum is still there and the Gift Shop was demolished. At the back of the Gift Shop was part of the old building.
There is now a fudge Shop where the Gift Shop was and also a vacant shop next door
The rest of the building has also been replaced I believe into flats
So you were quite correct but afraid I cannot tell you anything about the black cat!