No the TB03/Evo5 Diff or spools dont fit the TB03/Evo3.
I suggest you to get these ones!
They should fit directly, and are a great hopup.
I use it in my Evo4, wich uses the same diff joints, and in combination with ceramic diff balls it works supersmooth.
TT01, F104, TRF415MSXXMRE07, TB Evo5 Exoten, TB Evo6, TRF417v7, TRF 418........