It's widely assumed that a lot of Cessna parts aren't available anymore, so just about any price is worth paying. These folks get myopic and never look anywhere except eBay. It's like they never heard of Google.
I get several calls a week from members or potential members who are looking for a certain part and want to know where they can get it. I usually locate at least one source, sometimes several while I have them on the phone. My secret bag of knowledge? Google.
