With this model when the bearing goes bad it is just not economical to replace the tub assembly. However if you want to pursue it I suggest to obtain a service manual, which I believe are downloadable from the internet for a small fee. Whirlpool used to make these manual available but they no longer do so.

If you do not need a front loader, which has many problems as you are now aware of I suggest a basic top loader. It will do a fine job, last for years and if you buy one with mechanical rather than electronic controls it should be trouble free.