Nest Doorbell

[thisisreallyfunny]

We've just purchased a nest doorbell and are looking for a chime to go with it. We're having difficulty finding a 16v one, can anyone share their suggestions please?

We had ours fitted by a nest installer but he said he had to source things from Europe as he couldn’t buy the right stuff in the UK. We had no pre-existing doorbell. Sorry, no idea what it was he got, but maybe speak to Nest and ask what they suggest.
I have a feeling they knew there were issues as it took a few weeks to get ours fitted due to this, and oddly enough on the date the installer was coming they emailed offering me free fitting, which they honoured when I rang and said the fitter was due in 10 minutes! But an odd thing to email as an offer weeks after delivering the doorbell.