Doogs, all the boat trailers places will be able to help you out with bearings, they do them all the time.
If you're intending to travel far afield, it is useful to understand how to do it yourself. I found a few clips on YouTube helped me on my first attempt.
A few tips:
Use only high temperature bearing (HTB) grease, other grease turns to liquid when hot and runs out (personal experience, not pleasant)
Don't over tighten the crown nut when replacing the bearings, finger tight or just a little more to allow the split pin in perfect
Once you know what bearings your trailers uses, a spare set in the toolbox is cheap insurance
The hardest part of the wheel bearing jobs I've done has been to get the bearing off, as in each instance they've been well and truly stuffed.
