Derelict London is quite a well known site run by Paul Talling covering lots of aspects of the decaying crumbling city that we don’t always consider or think about.
There is a specific section on signs and murals which features a couple of brickads (see above). The Brymay matches one is in New Cross and I’d love to visit it if anyone knows precisely where. It seems to be part of a wider campaign as this example from West London shows. Also, I don’t know where the one in Old Street is, although I’m more likely to pass that on my general travels.