Expansion Tank and cooling fans for a 1987 Audi 4000 Quattro

[David Vanden]

The three blades will not be as effective as the four blades, I don't
think. No less,  Can you sell me an expansion tank this time that is O.E.
and is in decent shape.  Can you recommend a goof aftermarket radiator
cooling fan for that car since I am having problems getting used ones in
good shape?
Remember it is for the 1987 Audi 4000 Quattro.

David Vanden