EIKI LC-XB21B /Sanyo PLC-XW57 lamp ballast repair

[Moij2x]

EIKI LC-XB21B /Sanyo PLC-XW57 lamp ballast type RPB-7491EA dit not ignite HID lamp.
I find diodes D5, D4 and zener CR1 are dead.
What type of components can be used for replacement?
Diodes are marked as 83A, seen on image.
I had not find schematic but traced schematic power part form board, supply power is 280V DC, load is 200W HID lamp.

[Moij2x]

From http://www.fixyourdlp.com/2018/07/28/ignition-and-connections-in-authentic-projector-lamps/  I find information that ignition impulse voltage for lamps used in this type of projectors can be about 5000V.
Maybe this mean that diodes must have  max reverse voltage 2500V? I not find any of so small (case is 5 mm long) diode have so high max reverse voltage.

[Moij2x]

Zener marking is also unknown and replacement cannot be find.  It is GVY86 or VY86G or Y86GV or ... but Google did not know any of this combinations.

[Moij2x]

If CR1 is 86 V zener, did this make sense?
Can this schematic then generate HID ignition impulse?