clutch piston part number 23131464167

[maxt]

Hello
I need help regarding right part of clutch piston on my K100RS 85.  I am little confused  on my  K I have parts  from picture below 1st and 2nd pic (part No2) , but part which I found with same BMW number looks totally different  3th pic, does anyone know the right number of parts ? or question would be  if this fit  to my bike.. 

[Inge K.]

#1 is from a R modell
#2 is old K version that is NLA from BMW.
#3 is the new K Version, with piston and bearing sold as one piece.

Motobins in England have both versions.

EDIT: Motobins don't have the older piston anymore, only the bearing.

[maxt]

Thx for answer yes I already checked their website so they don't have it, mine looks really scratched so if there is no choice for replace I will keep this old one / I will replace just bearing on it  / ...