We have bought and sold thousands of items using Ebay and never had a problem so if the seller you are buying from has a good star rating and feedback (both easy to check) there's usually no reason not deal with them. I've bought everything from a £10,000 motor and a £15,000 boat to a 50p toy from all parts of the world and only been disappointed once with not concluding the deal. Just be sensible and follow Ebay's methods of payment and you should be ok.
What is his username and maybe we can give you an answer....
Like Althorne, I've bought and sold lots of items on eBay - only had one potentially bad deal and but the seller refunded payment when I discovered it was not as described.
We still don't know which one you have in mind. There are quite a number.
If it is Peter Davies' shop (gilda1956) I have always had excellent product and equally excellent service. The only hinges I have bought from him was a pair for my forehatch.
I have no connection with him other than as a customer.