I've got 6 NOS IN-18 tubes in individual boxes I bought a while ago for a project that I don't think is ever going to happen.
If someone here wants to make me an offer for them, I'm probably going to accept. I've also got a handful of original ceramic holders for them as well as some small tubes originally planned to be colon separator lights.
FYI I'm in France, so p&p outside of the EU might be a bit steep. But I will post anywhere.
More details if required: just tell me what you want to know.
Cheers
Bill