Interesting circuit; I haven't seen the resonator used with tubes before, thus I can't comment on that.
In addition to the other comments I have a few more:
- Capacitors of the "5" series (C2, C4, C5, C6, C8) are usually hard to find these days. Perhaps consider the much more accessible "4.7" values?
- Z2 is 1A, which is typically quite excessive for +B. A slow blow fuse rated for less current would not be stressed by the inrush current during power on, and the protection would be more effective.