Hi!
Thank you again for a nice reply. But unfortunatelly I must correct you - valves are not avaialble as a separate part from delaer (Graupner) in Europe. You can buy whole valve assembly, which cost around US$ 50 per valve. I carefully read the papers with the engine and with the OS .91 FS Surpass II engine in the shop - you have part numbers in original OS engine booklet with the exploded view of the engine, but with the german translation (and in catalogue is the same) the parts list contains less parts and no exploded picture of the engine. The answer is that the rest of the parts can be only installed with the OS serviceman in Graupner - and unfortunatelly cannot be bought.
Leroifort kindly offered me help - I hope this will work. Otherwise I will order the valve springs at Justengines in UK, which offer really great service to its costumers.
Thank you very much again
Sašo