Up for sale here is this brand new replacement power supply relay for the Onkyo M-504, M-506SR, M-508, M-5570, M-5590, and probably others as well.  This will replace any of the three relays in the Onkyo M-504 and probably the other models as well.  It is fairly easy to install as long as you know what you're doing and have a decent soldering iron. I will email you installation instructions when you purchase this. For some installations you will need to trim some pins off, so just line up this one with your old relay and you can see which pins to cut. Please see my pictures for details.

US shipping and handling is $5, and international is $18, no matter what quantity you buy. All my small parts are set up for combined shipping, so just use the "add to cart" feature and then check out all at once, and it will combine shipping. If you have any questions, please ask.

Looking for more parts? I have power switches, feet, pushbuttons, top case screws, bottom screws, faceplate screws, white LED fuse lamps, blue LED fuse lamps, 6.3v bi-pin bulbs, 8v bi-pin bulbs, 12v bi-pin bulbs, wired 8v 60ma bulbs, new power cords, new main capacitors for the Marantz 1060/2230, wired Pioneer speaker plug replacements, new 630v yellow film capacitors at 38 different values, new 1200v yellow film capacitors at 15 values, a large variety of transistors for vintage stereo repair, new Wima film capacitors for stereo repair, new 250v yellow film crossover capacitors, and more. Just use "add to cart" on everything you want and then check out for combined shipping.