Realistic price for a 1971 Les Paul Custom?

[Basvarken]

A friend of mine is offered a beat up old Gibson Les Paul Custom.
With gold hardware (in most places the gold is worn off)
A third humbucker is installed in between the original old PAF pickups.
The black finish is checkered, and the back of the neck has several bare places.
There are several plugged holes in the control area.
The silver reflector cap knobs look like they've been under water for years. One the knob is missing the chrome cap.

Guitar plays great and sounds real smooth.

My best guess of a realistic price would be 900 euro.

What do you guys think?

[Psycho Bass Guy]

That sounds about right, though I think he should open with an offer of 800. The missing PAF and plugged holes are the major negatives.

[Hörnisse]

If it has actual old PAF pickups then that is a great offer.  My old '72 had patent number pickups.  No dot on the "I" either. 

[Basvarken]

Thank you guys.