Tee Nee did not use anything special for the hub as far as I know so you can get 99.9% of anything you need at a local auto store or home depot or maybe even wallyworld. Do you need the entire hub assembly or just the bearing/race part. Many boat trailers will come in two different size axles so if you go shopping bring along an old part that you need to replace. Here's a link to a home depot kit just for your info not necessarily what you need but to let you know what's available. There are four and five lug (bolt) hubs so make sure you search for the right one. Prices range moderately but get something that has good quality USA manufactured bearings and races and during assembly make sure you pack the wheel bearings with a quality water resistant bearing grease.
Look at your axle when you remove everything and make sure it is not scored or worn. If that is the case you would have to replace the axle shaft. Those parts are also available sometimes at a local farm supply dealer or online.
Hope this helps.