Have you tried Eurospares?
Yes but In the Eurospares they are 3 References:
Ref................Qty Fitted...............Part Number..............................Description
a) 001...................2 ....................386600012S..................... HOCK ABSORBER - -Valid from ***. Nr. 4681-
b) 001...................2................... 386600010..............VARIABLE SETTING SHOCK ABSORBER OPTIONAL - -Pre-modification: Up to Assy 2116-
c) 001....................2.................. 386600010 .............. VARIABLE SETTING SHOCK ABSORBER OPTIONAL - -Pre-modification: Up to Assy 2116-