Older model red BMW 650 motorcycle FOR SALE

On behalf of Nigel:

"My Dad passed away and I am trying to sell his bike.
It is a red BMW 650 motorcycle. For rebuild or spares.
Was originally bought to SA for the Durban Tatoo as part of the German Police display.

The model must be somewhere around 1982 or 1983 or maybe a 1985.
I have attached a pic of a similar bike (below), although the exhaust and mirror stalks are not black, they are chromed.

I would be grateful if you might be able to give me some guidance on what it would be worth if it was running, if it needed some tlc and if it was sold for spares?
One never knows the value of these things and although am not looking for a full price, also don't want to be totally ripped off.

Thanks,
Nigel
082 463 4946