Through Hull Problems

[gatorbait]

I have a 1977 20' Seafari, and the self bailing fittings at the back port and starboard side of the deck are leaking into the bilge. I've heard that these can cause big problems over time and sometimes need to be replaced. I'm having a tough time finding hardware other than through hull fittings designed for water pickup or for bilge output. If anyone can point me in the right direction or give me some repair tips for this project I would really appreciate it, thanks.