Pre-war CRT in Dr Röntgen's rays

[LENINGRAD T2]

It was an interesting project of rebuilding an old CRT. Many people got involved in this work. Today it would be difficult to find so many enthusiasts. Was such a reconstruction later repeated? I suppose that the number of old working CRTs available today exceeds the number of preserved TV sets. So there is no need to consider rebuilding old CRTs today outside the scope of the experiment. Of course, I may be wrong. There is undoubtedly a demand for the color 15GP22. This would be a very complex project. In my country, there are still available CRTs from old Russian color TVs. They can be used as a donor. Of course, there is another problem with the 15GP22 related to its modular construction. 
Returning to the 6/6, what model of a more modern electron gun could be a substitute for the original version from the electrical point of view?

Adam