If you are going to do all that I would just go with the disc brake upgrade if you are going to keep the trailer. The folks at Performance Trailer Braking came to my home, replaced axles, springs, suspension, shackles, installed MorRyde Xfactor cross members and disc brakes. I know they go to some places in the NE but you would have to check with them. Phenomenal service, installation and folks. Their link;
https://performancetrailerbraking.com/