WTB-Trailer bumper/guide

Not exactly sure what the correct name is, but I need a rear starbord side bumper/guide for my CC trailer. The boat is a 69 CC Mustang and although I've read posts where people are talking about trailer #2, #3, etc., all I know is it's a trailer for my 16' CC. I also know the trailer is from the mid 80's. The original side bumper rusted off on one side.
In case what I'm looking for still isn't clear, it's the relatively tall 4-5' pole with a black ruberized coating that helps get the boat on the trailer straight. Pics available if needed.