I've been fishing down there for the past 10 years.
There is little in the way of bait available in the few local shops that sell tackle.
The shops in Clonakilty and Skibereen had frozen sandeels if I remember correctly but little else.
I usually stock-up on peeler at Halfway Angling Cenre, Balinhassig :
https://www.tackledirectireland.ieLug, white rag, razor and clams can be found on some of the more sheltered beaches, you'll just have to explore and find them !