i have a ppl licence with around 50 hours.
Congratulations on getting your licence with so few hours: you have only 5 over the minimum45.
Unless you mean you have 50 post PPL issue hours.
Which brings me back to my original question.................
I would agree with the other posters: Just rent an aeroplane with an instructor, fly from LHS and shove your mates in the back.
I did this (no mates in the back though) from Westair Aviation from N Las Vegas and landed at West Grand Canyon airstrip (Owned and run by local Indians) about 10 years ago.
Much less stressful for a first venture over some of the most hostile terrain you're ever likely to encounter.
Oh and one tip: Go as early in the morning as you can as by midday it gets seriously convective and you'll get a pretty rough ride.
Cusco