I shot this on Mercator Trading's table at Sandown Park last November as a new to hobby name, so it should be newish to Internet and is certainly new to Blog! Lambert Brothers of Acton, North London, nothing else known!
The farmer appears to be a poorer copy of the Fylde one (Joplin, pp127), the fencing a sub-copy of Britains, while the chickens seem pretty unique, but the larger animals look like Benbros (Joplin, pp23) who also do the farmer, so a better clue there, as to where Lambert's may have got their (Christmas?) stock. Thanks to Adrian for letting me shoot these.