Yes, you can simply replace the prop shaft - balsa pr.com or aeromicro.com.

For a simple upgrade to give you more power get a Graupner Speed 300 - it pops right in, and is the equivalent/exactly the same as? of a GWS 350.

Lots of people seem to prefer the 12x6 to the 11x8 - I just bought some HD 11x7's so I'll be interested to see how those perform.

If you really want some power, go to an MP Jet 25/25-26 or 25/35-20 - those will get your camera into the air!

Cheers, Phil