Tourneo interior lights

[doebag]

The interior lights on my Tourneo, rear passenger and rear loadspace, are wired to operate in tandem with the front interior light above the rear view mirror.
I am looking to adapt them so rear passengers can turn their overhead light on without the need for them all to come on.

I need a suitable sized light but with a switch built in, and then I need to run a switched earth wire to an earth point.
My problem is finding a suitable light. Searching on fleabay just throws up hundreds of ford interior lights or LED bulbs.
Anyone know of a suitable light to save me a month long search.