Buddy bearings are typically those that are put onto the outside in place of a dust cover cap in order to squirt grease into. From your description, I assume you have the grease fittings on the end of the spindle. That being the case, the spindle contrary to what you say is part of the axle which the bearings go onto with the racers. If that is bent, you will have problems with bearings failing and that sir is not good at all. Then a new axle is a must. I learned as a dealer in the beginning the hard way. You do not want to put your family nor yourself in an unsafe situation pulling a trailer of any kind.
I believe in the Toledo area you would find a trailer supply house and as noted in the forum, there are places that will ship to you as well. Generally there are markings on the axle.
In addition to the master cylinder rebuild, again you should be able to find that at a trailer supply. The manufacturers basically use the same style one for drum and the other for disc. I wish I could remember but I have been out of the business for a while but a good trailer supply will be able to help but be careful as many salesmen do not know what I would be talking about as they would try to sell you a whole unit which is bunk.
One thing I will stress and that is repairing your trailer. Do not take safety out of the factor sir. You are risking the lives of anyone to include yourself when you tell me transporting a boat on an unsafe trailer, That is something you do not want to consider.