"Track Rod Ends has very slight play, both sides."

This doesn't mean they are knackered.  If they are a bit loose that's
normal, they should be replaced when the ball starts knocking in and
out of the socket.

The rear trailing arm bushes cannot be diagnosed as faulty purely on
mileage or be visual inspection.  You'll know when they're in need of
replacement as you'll get a knock from the rear when you accelerate,
you may have odd tyre wear on the rear tyres and in severe cases, the
rear axle will feel like it's floating and not really connected to the
car.

The rear trailing arm bushes were a problem on many early e36's, but
newer ones had the redesigned rear trailing arm bushes which had a
metal casing round the rubber bush, making them much stronger and
longer lasting than the earlier, all rubber design.

Most suspension/steering parts are made by BMW by a company called
'LEMFORDER' (or something similar!), so as long as you use those parts,
you are getting the OEM bits but without the BMW stamp and price.
Euro's and GFS usually do 2 options, OEM quality and a cheapo version -
the OEM ones can be OK, but avoid the cheaper parts form Eurocarparts,
etc, as they don't last as long, so it's a bit of a false economy.

Clutches are usually SACHS I think too, so again replacement SACHS will
be jsut as good - Euros sell some other make (name escapes me right
now) but they are used in Peugeots, etc....so have not rightful place
in Munich's finest!

OTher parts such as the viscous fan coupling are made by SACHS, and I
know when I replaced mine some years back the GFS unit was exactly the
same SACHS unit....

It's always worth checking with a BMW parts dealer what make the
original bits are and asking these parts places who makes theirs.