The most reliable Long Range Communications radios available covered by the Ham Bands are the ones called HF (High Frequency) radios as compare to VHF and UHF, Yep V for Very and U for Ultra.
The HF or Low Band Radios usually cover from 160 meters through 10 meters and the newer ones cover through 6 meter. There are Portable 100 watt units, but not really hand held. They draw to much current and would need at least a hefty 12 (13.6) volt car radio.
Compact ones of modern design such as the ICOM IC-706 MK II-G can be had for from $400 to $600 depending on condition. To that you would need a battery (can be set as low as 5 watts for low current draw and as high as 100 watts if you have the current available or a 110 volt to 13.6 volt power supply) and solar charger or some other way to keep the battery up and a Resonant Antenna or a wire and an outbound antenna turner. Radios like this also cover 2 meter VHF and 440 MHZ UHF bands. There are repeaters on the 2meter and 440 band and it could be possible that you can reliably get around (via a repeater on a nearby mountain) your obstacle very reliability using low power FM. These systems are set up all over the country by Hams and Ham Groups for OEM use as well as just fun and personal communication. (I have one for sale by the way. Like New with the box, original manual, mike and everything else that goes with it.
In addition to covering the Ham Bands in multi mode - Upper and Lower Side Band, CW (Morse Code) Am and FM, the newer ones have full coverage receivers which include AM Aircraft, as well and on UHF Military the military air band. Though they do not transmit out of the Ham Bands, they can be "Unlocked" and then will do so as well as being able to cover the marine HF bands. Many boaters buy Ham Radios for their off shore HF SSB set up as they are half the price of a dedicated Marine SSB unit with more features.
Hope that helps. Feel free to give me a call on East Coast time to answer any questions you might have.