transistors for marantz power-amplifier 250M

Hello to all,
like my subject stated i am looking for spare transistors for the marantz 250M amplifier.
There numbering is a bit strange (i think they made there own transistors or did number them with there own company numbers)
The numbers are as follows:

462-2026
461-2015
462-2021
461-2010

Any help on buying them and or datasheets would be very good.A explanation on the numbering or equivalent (modern) transistors is welcome too.I also need the service manual.

Many thanks in advance.

Johan,Belgium-Europe

Those look like internal Marantz numbers.
Here is the 250m schematic:
**broken link removed**