I highly recommend Standard Horizon HX 890 radio. This is a newer model than HX870. Actually HX870 is more advance version that HX890. They remove several features from HX890 which kayakers almost never needed.
Few thing I like about HX890 (I believe HX870 has same features)
Radio floats. You still have to tie down to your PFD or it could float away from you.
Built in GPS (you could track down your trip if you want then download coordinates to your computer. Nice feature I used few times. It could eat up your battery so has to be used carefully)
Comes with AAA battery case. Can use 3xAAA batteries.
Digital calling feature
MMSI – Can program your own MMSI (Maritime Mobile Service Identity) # to this radio. This can use for calling another radio by adding their MMSI number to your radio.
Distress button. There is an distress button on the radio. If you press this button, it will send a distress signal with GPS coordinate so that you don’t have to give your location verbally.
Flash light – I hardly use
FM radio – occasionally uses
Weather channels – all radios have I believe.
I bought mine from Steveston Marine at Langley. Looks like it is on sale for less price than I bought two years ago.
Please let me know if you need more information.