hmm i wouldn't know where you could get a manual trannie for it but you should be able to get a w58 from a 7mge supra and try and find a manual bellhousing for the 5mgeu - w58
you will also need the clutch master cyl & slave cyl and lines... maybe your best bet is try a junkyard and try to get all the conversion bits from a donor car
let us know how you get on