I have a 3AJ Tenere and my wife has a 1991 3TB XT600E.
I have worked on both of their engines and am sure that their starter clutches are different, and don't think that these parts can be swapped between our bikes.
From memory, the one way rollers grab the crank shaft behind the rotor and this area of the crank is different between the models, preventing using the (i'm told better) later parts. If it is used for too long with worn one way rollers, this area of the crank could be damaged.
If I were you I would check carefully if what you are being offered is listed for a 3TB, and if it is I doubt it will fit your 3AJ,, Sorry.
I think you also need to have a good look at that area of the crank shaft.
BTY, you need to scroll down the parts diagram to see the relevent bits.