Long Range Remote Controls waterproof

Hello All
First of all:
I am a bit of a fake when it comes to Remote anything.
However I appeal for your patience.
Presently I use Sensor R/Cs to control a large heavy and fast robot via the AX2500 fron Roboteq

Problem
I need a decent long range 600 yards Remote preferably weather and idiot proof I may even want to drop it occasionally.
A professional R/C system is no problem but searching one out on the internet is driving me round the bend.

If you could help me out I would be eternally grateful and damned happy :open_mouth: : :stuck_out_tongue: