Any decent brand will have replacement parts, though in the case of my Surefires I never had an issue, and these are work lights.
I did an installation job once with only my M3 as a hammer, the bulb had no issues taking the beating. That's why you pay a premium.
The prices are high, though you can rummage around on light dedicated forums like
CPF to find amazing deals, especially on used items. My M3 setup cost me a fraction of the near 1000$ sticker price.
That site also has the best resources hands down for these types of questions.