Vintage Synth Repair

hi all, i`m new here, and excuse me if you don`t understand my 
english, in my country people speak spanish.

I have an Arp Omni, somebody gave me it as a gift, i was trying to 
make it produce a sound, so i have opened it, and the power supply 
is missing. I have wroted to Peter Brown, and he told me that 
somebody here got the same problem, so i have a few questions for 
that person(s):

-As you know, from the power supply come out 6 voltages (i`m taking 
the reference of the schematics at the page of peter brown), do you 
think that if i produce that voltages with another power supply it 
will work normally???

-What amperage produces the power supply??

-I have a power supply of a PC, but can only produce until 12V, can 
i use it or is not enough voltage?

-The parts on the Power Supply board are still in production??