Up for sale here is this "Plus Ultra" rebuild kit for the Marantz 240 or 250 amplifier.  This includes all the parts you need to rebuild a Marantz 240 or 250, including two new main filter capacitors.  This is the Plus Ultra rebuild kit, which means it has MATCHED replacements for almost all transistors in the Marantz 240/250 (even the outputs), plus replacements for all electrolytic caps, many film caps, bypass caps for the main filters, all eight 0.15 ohm 5W resistors, four diodes for the diode mod, and a replacement relay with adapter board.  I also offer a more basic rebuild kit for the 240/250.

This kit includes:
2 main filter capacitors (Chemi-Con 22k uf 80v)
17 axial electrolytic caps (Supertech)
8 axial MPT film caps (Supertech)
4 radial film caps (2 Panasonic film, 2 Wima)
18 transistors (replacements for all board transistors, all HFE-matched)
8 output transistors (HFE-matched Onsemi MJ21195G/MJ21196G)
4 1N4007 (for amp board diode mod)
4 TO-220 mica insulators
1 1" piece of heat-shrink
8 0.15 ohm 5W cement resistors (Supertech 5%)
1 relay
1 adapter board
8 header pins

This is the right way to rebuild a Marantz 240/250.  Yes, even if yours is working.  All the transistors need to be matched, and all the original transistors need to be replaced.  This kit took me FOREVER to put together, and involved a ton of research.  This is an expert-level kit, so you should have EXTENSIVE experience working on complicated vintage gear.

These are all high-quality brand new genuine parts, the same ones I use when I rebuild vintage equipment.  Capacitors are Supertech, Wima film, Panasonic film, and 2 Chemi-Con 22k uf 80v filter capacitors.  Transistors are made by Onsemi, Central Semiconductor, and Diotec, and the relay is a new Omron relay.  

This kit includes a total of 84 parts.  This is a very full rebuild kit--it is MUCH more complete than anything else out there.  This took me a long time to develop, and I am very proud of it.

This is not a quick and easy rebuild.  It will take a decent amount of time and effort.  The instructions will explain how everything goes in, but will not cover how to disassemble your amplifier.  This is a complicated job, so if you do not have a lot of experience with vintage gear you should not start with this one.  You should know what you're doing and have a decent soldering iron, a good desoldering tool such as the Hakko FR-301, and a dim-bulb tester with 75W or 100W incandescent bulb.

US shipping and handling is $12, and international is $36.  If you have any questions, please ask.