The Philips and ITT ZM10xx tubes were available 10 years ago, before the
industry sprang up; they are getting as hard to find as teeth in hens these days.
I'm still making nixie watches with B5870 tubes, as I have managed to secure a
bunch of these tubes. They do not look good in clocks, as they are too narrow,
being designed for calculators with a dozen or more digits.
I'm interested to learn if anyone is making clocks these days using anything
other than Russian tubes.