Hi, Any branded FULLY synth 2stroke engine oil should be ok as long as it's suitable for injector system's (assuming you have one).
Any branded gear oil classed as "light" (I think about a 40weight), holds about +/-750mls.
No point harping on about this brand or that brand as I don't know the exact composition of each and every oil on the market, 10 people will have 10 opinions and all that.
Regards Phil