Sorry for the delay in getting you a reply -
I used coversearch.com for our cover. You get a cover made by Carver Industries and it has served us VERY well. Plan on a cost of $600 tp $650 or so (cant remember exactly).
Others recommend boatcoversdirect.com. The cover you end up with is the SAME cover. I happened to use coversearch as I found the phone service I was able to get was very helpful in getting the right size for our 228.
Anyway the model number we have is 1C-90025. It is 8oz. marine polyester and has held up VERY well.
Here's a pic for you: