Hi!
As you are from Europe as I'm, you will find that the Russian MDS engine works fine on low nitro (5-10%) and 15% all synthetic oil like Graupner Aerosynt 2 and Aerosave or The French Motul "micro" syntetic oil.
Castor oil could ofcourse be used but the engine will run better and hold up longer if you use only syntetic oil.
As for propeller: Always use the American APC line of props if you want good performance and if you want a fiberglas prop (As most flyers do nowadays). There are wooden props but these are not any better than the APC, only lighter (which could be good sometimes). Menz is one of the best woodprops.... but I don't think that they have as small props your'e looking for.
A 10x6 to 11x6 is perfect for a highwinged trainer aircraft like the Kyosho "Trainer" (at sea-level) and for most lowwinged sportaircraft.
Enya 3 or OS 8 are good glowplugs.


Regards!
Jan K
Sweden