Well, after unsuccessful attempts to buy spare part in the store I made my own "homemade" tool for rubber tube that is part of shock absorber:duh
[ame=http://www.youtube.com/watch?v=FJ8Nh2Kl3KA]Tool for making rubber part for shock absorber ( Mares Sten 11) - YouTube[/ame]
[ame=http://www.youtube.com/watch?v=FJ8Nh2Kl3KA]Tool for making rubber part for shock absorber ( Mares Sten 11) - YouTube[/ame]