Amp repair

[ddino77]

I own a Technics SE-A3 stereo amplifier (circa 1981-83) rated at 200 wpc, which I believe has shorted output devices (keeps blowing fuses).
The manufacturer Technics (Matsushita) discontinued all parts for this unit. Can you help find alternative transistors?
The original 4 transistors were labeled OD-503AP (long rectangular shape) mounted 2 per heat sink with
6 pins each. The replacements might be MT200 with 3 pins each. Also, Is there a facility that can be recommended which
can either help me repair/rebuild the PCB modules/drivers boards/output devices? I would greatly appreciate your assistance. As you can tell I only understand the very basics.

best regards, dan

I am also including the following link which belongs to a repair facility in Japan which has experience and familiarity
with these amplifiers and which may help ID the transistors. Unfortunately I tried but have been unable to contact them directly.

www.http://www.geocities.jp/tsoka/surind.htm

[tiltedhalo]

nowcomponents sells replacements, probably will cost a pretty penny and require a minimum order, so does spacecoast components.
The originals are proprietary parts, basically a pair of NPN's and PNP's on one die. with a little work you should be able to cross to normal 3 pin TO220AP pacs with similar specs.