I've shared on french forum my research recently, I've translate it for you here, hope it can be usefull
For Astro/NAC/Egret2/etc...
I've found Tube compatible for both spec and curve (not the easiest one)
Tube Toshiba A68KLF96X
Toshiba : 2929DD , 2927DB
It's possible to install a MS9 + yoke
Otherwisen it's also possible to use the TV chassis in a cab because it's not a 100Hz and the picture quality is pretty good
For Blast/Windy2/etc...
I've been able to found original tubes from Blast in a lot of TV for which the list can be increased for sure
Tube Toshiba A68KZN696X
Grundig : ST72-261 IDTV/LOG , ST72-261/8 IDTV/LOG , E72-911 IDTV , M72-105/9 IDTV (PIP) , M72-105 IDTV , ST72-160 IDTV , E72-911 , M72-795 , M72-795/9
Tube Toshiba A68LBT696X
Grundig : M72-410/9 Reference , Sydney SE7230 DOLBY (VNM) , Atlanta SE7250 PIP/DOLBY (VNM) , Atlanta SE7250/8 DOLBY (VNM)
It's also possible of course to use those tubes with MS2930/31 + yoke but not only. some models have built in VGA port and are compatible for 480p native
But all those TV chassis are useless for 15Khz because all TV are 100Hz
For example, the M72-410/9 Reference is pretty good at VGA
For NNC/Naomi (Flat)
I've found a TV with a tube from same familly (spec + curve) as the original Toshiba tube of the NNC
Tube Toshiba A68LQP356X
Grundig : Xentia MF72-490 Dolby
It is possible to install this tube in a NNC with the Toshiba + Yoke chassis. It is also possible to use the entive TV directly in the CAB (direct drop off) because this TV have VGA input and directly boot into the proper input.
The picture quality is so good that I use it as daily driver for my Dreamcast and Naomi
Hope this helps.