Really! You are towing a trailer that is 13 years old. you have tires that old. that's not even something I would brag about. get them replaced NOW. the dry rotted valve stems should've been the first hint!
Now you find your bearings and brakes need attention! again 13 years and you only added grease to the rear bearing instead of doing a complete repack? and didn`t even install new seals! and you know you need brakes but are going to wait till next year when you already had it all apart! Why?! do it and be done. why take the chance? I would do it and be done and safe.
And why go with cheap tires, especially 14" go with name brand and again you wont have to worry.
:?