Lots of good reasons to always fly with a radio, including emergency help in places where cell coverage is spotty, and finding out about changes in the weather before launching or while in flight. Many thread on the topics already but this is a short summary of info on those prior postings.
A good inexpensive radio is the BaoFeng UV-5RA. About $26 shipped on line. They are legal for us to use on the USHPA frequencies if an instructor gave you the USHPA radio test. It is illegal to modify a radio but the Baofengs don't need to be modified. Key thing about the UV5RAs is that they have LiPo batteries that last a long time. Most of the antennas they come with are poor, but they work and you can buy a really good antenna for the for another $25 (search for a thread on antennas). Some of us have cloning cables that can copy the pre-programmed settings on our radios to new BaoFeng radios in less than a minute making setup easy. For PGs you can get a hand held mic option that works as an inexpensive Push To Talk (PTT) alternative. For HGs and PGs looking for a PTT, Baofengs connector is the same as Kenwood radios so look for Kenwood PTTs.
NOTE: USHPA use is Secondary on our frequencies. These are Business band frequencies and they have priority use on them. At Lookout and Boulder we use the worst frequency for radio and antenna efficiency (158mhz).
It is best to get a HAM Radio license so you can use these types of radios on the HAM frequcy bands as well. If you have a HAM license you have little to no risk of having a radio confiscated and the test is easy. You will be taking the test with pre-teen students who can pass it, but it does require some basic tech knowledge so it is best to find some free on line test prep sites to study for it. Then take the exam for about $15 and open up ways to use the radios with repeaters that get much better distance and reception if you go on that very long XC flight and land in the middle of nowhere.
One of many HAM test prep siteshttps://hamexam.org/
Link to when and where to take a HAM examhttp://www.arrl.org/find-an-amateur-radio-license-exam-session