Golf GTI cabriolet 1991 fuel sender wanted.

Fuel sender for golf GTI convertible part no:- VW 533919051f  . Can someone help please?

Here's mine seen better days… 

Remove the pump and connect hose
I would carefully take the electric rheostat out of the case.  

Then soak the metal bits in Vinegar for a day or so and knock the rust down.

Test your rheostat using a DVOM, and if it is good and all the bits are de-rusted, then re-use it.

Repairing your Fuel Sending Unit | Volkswagen Owners Club Forum