This morning I've received a message from an ebay seller in Japan that Japan Post is not currently airlifting mail to the UK so he can't currently sell me a bottle of ink. I have no reason to believe he wouldn't sell one to me if he could so must assume he's telling me the truth.

I will check out what the sellers at Rakuten say, but it may be that they have the same problem. If I get a price that is over £25 then I would rather just buy it here at £29. It's easier.