I have 2 chandeliers from London (I live in the US) and they take double bayonet based bulbs. I was told I do not need to rewire the fixtures, but instead need to get the right light bulbs. Is this true? I have tried finding some but they are all appliance bulbs and when I inquired about them working for the chandeliers, they said they were unsure. Can anyone advise? Thank you!

Since the UK uses 230 volts, and we use 120 volts here, that is not an issue.

The UK color code is blue is neutral, here white is neutral.

You would need to find 120 volt lamps to fit your lampholders.

One word of caution, and electrical equipment connected in place in a building in the USA must have a UL listing.

If there is a problem in the future with these fixtures, a fire for example, the UL label will be the first thing an insurance adjuster will be looking for.

No label, no claim, your left out in the cold.

Getting the right bulbs would solve the problem.
The problem you're going to have is that incandescent bulbs have been phased out in favour of fluorescents in the EU.
There are still some places that have incancesdents stockpiled, but they are no longer being manufactured.

If you're happy with fluorescent bulbs, eBay might be a good bet.
If you want incancesdents, lets face it chandeliers look better with them, changing the fixtures will be a better idea in the long run.