Balloon flight / helicopter flight

Hi

Me and my friend will be visting Kathmandu on the 15 Oct for 7 nights and would like to do either a balloon flight or a helicopter flight over Kathmandu and suroounding villages - not so much the mountain ranges.

If anyone could suggest who we can book it through - or not to book through!! that we be great.

We have a max budget of US$ 250 each.

Thanks for your help

Carole xx