I'm not sure of the regulations for air transportation but they can either travel with you as baggage or they can be sent in advance as air cargo. The club will arrange customs clearance. Unfortunately we don't have parajets here but I have a spare tank for a PAP (new style) that could be used and the club use HE and they have tanks for those. Batteries shouldn't be an issue to obtain here as long as they are not special to type.
I do fancy the idea though of getting a second hand parajet!
I'm trying to get prices for flights and I'm going to talk to BMI to see if we can get a package deal. We are also trying to ensure that the only cost to yourselves will be the international ticket element and the cost to get your equipment here. The internal flights, accommodation, food etc should all be free. So as long as you can spare the time there should not be any cost difference but even if you can only make it for 7 days it should be worth it.
I'll keep this post updated with the latest info.
Alan