The trouble you'll have around the ealing area is the general lack of a GW store. You can check with the GW storefinder for which is closest to you but there is a bit of a black hole in ealing itself.
to be honest the void stretches up to much of north london ever since the store at brent cross shut down. I sometimes head to west finchley where there is a club called the titans that meet. Its not exactly west or sw london, but its easily accessible on the northern line (literally right next to the station)
I haven't been in ages though so can't say what sort of state they might be in.
heres a link