Vintage sink with small waste & lead washer seal... what to do?

[jjkenya]

First post... here goes:

We've acquired a second hand but lovely old sink which I've been tasked with plumbing in. The existing waste (plug/hole) is small - about 23mm ID. The lock nut on the bottom has a large lead "washer" or seal of some sort (I'm sure there's a plumbing name for it) which I think used to have some kind of sealant between it and the ceramic, but that's all cracked and dry now. The overflow is a weird ceramic cast overflow... photos will help explain.

The thread for fitting a trap to the sink waste has an OD of 28mm as far as I can tell. I just have no idea what to do next:

1. Try remove the whole lot (and risk cracking the sink)?
2. Leave it and try connect on to a plastic trap somehow?
3. Remove it, clean it up and re-install the waste and thread (and then do (2))?
4. How do you deal with that overflow?

I am pretty sure it would have been connected on to lead pipe back in the day... Not sure why that matters now. If anyone has any ideas, such as where to look online to find these old fittings, or perhaps what thread it's likely to be, or what size the waste is "officially", please share.

Thanks in advance.

 

[snowhead]

I'd strip the waste out ,, carefully otherwise you'll end up replacing it after it's been fitted.

Caravan waste / trap would be the solution, they're small.
https://www.caravanaccessoryshop.co.uk/category/sink-fittings/123

 

[snowhead]

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