Manual box oil yes- oil is special Volvo synthetic only available from the
dealer AFAIK- but you may find a substitute if you speak to a knowledgebale
oil specialist.

If the timing belt was replaced at the correct interval then leave the water
pump til next belt change time.

I would replace the clutch slave cylinder- they sometimes go to leak after
being disturbed- an arse if you have to it after the clutch change.

Otherwise ensure a competant mechanic does the clutch- its not a job to be
rushed or corners cut on the transverse engined volvo's.

Tim..

Crankshaft oil seal. Don't know for '99 models, but on earlier models they all
start leaking after a while. Seal costs near to nothing. So if you're working
in that area and you decide to replace it right now, you may save yourself a
lot of money in the future.

Good luck!
Marc