RE: Where to buy Mejzlik Props?
An 18x6 prop might rev a little higher on the ground, but is not likely to be an improvement in the air. Lack of air speed is the problem. 8 inch pitch works a lot better for an aerobatic plane with an engine spinning in the 8500-9200 range. The 17x8 APC is one of the better choices. You might try a wood prop like Silversurfer mentions - I would try a Menz-S 17x8. If you could borrow a Mejzlik 18x6 prop for a test flight, I think you will find that it is not an imprvement over what you are already using.