Vintage Synth Repair

I have now small problem with power supply inside my Kawai K5000W.

I moved to Japan from Europe and there are two different voltages in  
my studio (220 V and 100 V) which can be dangerous. By my mistake  
Kawai got 220 V, not 100, because I changed internal connection on  
PSU when repaired FDD, and after returning the instrument back to its  
place in my studio I didn't realized it and used 220 V (cabel end was  
the same).

Fortunately transformer survived, 17 V symmetric section works. 5 V  
section gives only 0.5 V on output. Zener diode D8 is OK after  
measuring outside the PCB, so I hope that all following PCB's with  
digital circuitry survived... This diode is unfortunately the only  
protection.

So it looks I need to change these components:

F2 - ICP-N25 (IC Protector)
U2 - Mitsubishi M5291P (DC/DC Switching Supply Converter/Regulator)
Q1 - Sanyo 2SA1641 S/T (transistor)
maybe  Q3 - Sanyo 2SD1246 S/T (transistor)

I tried different shops on net, Japanese, American (of course  
Digikey, Mouser...), but they haven't these components. Neither I  
could find some substitutions (maybe U2 can be substituted by  
MC34063AP1, I have to compare datasheets. Does somebody know  
equivalent types?

Could somebody please recommend me some good shop anywhere? I'lll be  
grateful for any help as K5000 is one of my favorite instruments...  
Of course even after PS repair there's a chance digital circuitry  
didn't survived despite that double protection and Zener... In that  
case I must buy whole instrument, or at least K5000R rack version...

Service department of Kawai Japan headquarters in Hamamatsu refused  
repair, I have called there. They don't do any repair or sell parts  
for instruments older than 10 years, maybe it's some new law in Japan  
because Yamaha has same policy now.

Thanks for any hint.

Daniel Forro