iused to restore the edwardian geometric floors about 20 years ago and used to get replacement tiles from lassco reclamation yard.
they have a couple of yards in london.
drummonds in hindhead also used to do them.
the problem i used to have was that apparently alot of these tiles were cut on site and they can vary in size from one house to another in the same street.
there are estates like lion estate in fulham and barnes where every house had entry hall and steps/path done.
if you havenet got much work at any time .
put a flyer through every door on those roads in lion estates advertisnig you restore these floors .
it used to keep me vey busy .