Just some advice ,2 things you should not buy second hand are PFDs and Helmets, regarding safety etc, PFDs have a life span, while a second hand PFD might look nice and shiny if it doesn't float as much as it should well it could be game over , same with helmets , helmets are rated for 1 impact, you may not be able to tell if the helmet has had an impact or not.
Buy this equipment New
You can buy your dry gear and your boots, spreydeck boat paddle and everything else second hand.
Regarding which PFD to buy, I have an Astral Green Jacket(covered in dust), excellent PFD, I would highly recommend, however very expensive could be 200+, Palm have a wide range of PFDs, Check out ICANOE and Great Outdoors In Dublin, if you see one you like check if anyone in the club has one to get sizing right. There are a few local shops in cork but they wouldn't have the best selection or the best price in my experience.
Things to consider also are do you need a cowtail strap on the PFD and the size of the pocket.
Im sure some sellers of second hand equipment may disagree with what i have mentioned above, but its worth taking into account.
If you have any questions ask any of the instructors or familiar faces in the club will be happy to help