Trying to fix 2nd gen Front end need help finding the right parts... >:(

Hi everyone thank you for taking the time to read this.
My grandpa owns a 2nd gen with 4.0 v6 and it is starting to show some signs of its age, chiefly in the front end. Now fixing it is not the issue, but I seem to be having troubles figuring out which parts to buy, after calling the parts store they tell me that there is an abundance of parts and it will not be an issue to track them down, but on every part we find there are 2 different kinds base model and then just regular parts. Now his is the Sr5 model w/4x4 as well he says it has the TRD offroad package, so does this mean he needs to buy the regular parts or are the base model versions just a more cut rate part? At first I thought it may be a difference between the X-runner model and TRD models, until doing some research and finding out that there are the 2 different versions of TRD, any and all help is really appreciated as I cannot find anything about this online and have been searching for the last 2 hours and am really starting to get frustrated. Thanks Again!

 

I always just chose base model for my 03 TRD. Front end components ae all the same for them as long as you buy for 4x4 or 2x4 depending on what you have.