One of the most important pieces of essential gear you can bring out onto the water is a VHF radio, especially if you travel solo. The Irish Coast Guard issue regular weather updates and when you are a couple of miles/kilometres out at sea there is something reassuring about hearing the coastguard punctuate your day with their regular updates. Make sure you have your device fully charged before you leave the shore and it never hurts to have a set of spare batteries stored in a waterproof container on your person. An emergency radio is useless if you do not have ample power to operate it.
I use a small, handheld radio that can be clipped to the front of my PFD. It is called the Cobra MR-HH125 and they can be sourced on eBay. It is cheap and cheerful but it serves its purpose and I don’t see the point in spending big money on an item that will have to be replaced regularly enough. Saltwater and electronics are not good bedfellows and most electronic gear will succumb to corrosion at some point. The Cobra can be sourced for around €50 and to me that is a small price to pay for something that could potentially save your life. I certainly value my life at over €50, do you?
VHF radios are like seat belts in a car – I hope I never need to rely on one but if I ever do I will be glad that I am wearing it.