This SPEEDOMETER (MODEL S) assembly utilises five Bulb(12v1.7w,wb372,t7)(s) - the highest specified component.
The thirty Gsf600u 1999 (x) Germany (e22) Speedometer (model S) component parts are all listed in this schematic.
The most reasonably priced component used on the Gsf600u 1999 (x) Germany (e22) Speedometer (model S) is the Bulb(12v3.4w,t10,bf175-01450a).