Maybe get some indication from Octopart[0], quick scan tells me that there are relevant prodcts by at least TI, Fairchild, STMicro, Intersil, Maxim, New Japan Radio, Diodes Inc., NXP have parts in stock. I'd be surprised if those are all just old stuff and not still being produced.
digikey hardly sells everything, but they do sell various 555 chips from 12 manufacturers, at least per the parametric search.
Its fun to look at the weird options available. A UFBGA-8 package is available... weird, never used one of those before. TI sells chips that go up to 3 MHz. TI will also sell bare dies if you have a wire bonder. Supply currents are available down to 30 uA.
Buying bare dies would be really convenient for my die photos / analysis, but unfortunately with the Digikey minimum quantities, I'd need to buy 25 @ $4 each which isn't worthwhile.
