The rubber eye piece NSN is not mentioned in the blue user manual that comes with the sight or in the AESP and was the one of the only things beside the lenspen we couldn't get through the supply chain at a field unit level. Most of the C class or cosumable type items you can demand.
You can get the AESPs from DR TDOL on DII. When demaning these items cross check the NSNs from the AESP with SCOC if you can, IIRC the blue handbook is the US NSNs. When tours finish this eqpt get pushed back throught the system to be turned round and comes out serviceble and complete to CES; they are more than aware this sort part goes diffy. I hope this helps; the eyepiece normally never comes back as most guys shit- can them or lose them pretty rapido.