hi answer to my own question - after 2 days fiddling - -but cheap and cheerful solution.
It seems the lock barrel only with 2 keys is approx £260 with setting keys to the transponder best avoided by me if possible,
As the plunger did not depress far enough to remove barrel, drilled the plunger out, having removed steering lock assembly by drilling out the shear bolt heads (you can get these out with a punch by punching round the heads to take out the 2 bolts). The lock has anoth 2 rivets holding the face plate th the barrel outer case and a small pin at the bottom through a lug. Once these are out the barrel comes out - my problem was the one of the tumbler springs had come dislodged. Took out the 2 pawls for that tumbler slot and the springs which just leaves a 7 lever lock, perfectly ok does not really affect the security as the imobiliser covers this. Back together ok.
Toyotas are good cars but the cost of some parts is ridiculous.
keith myhill, February 2008