Have you posted your request on the Airflow Forum?
If not ask the question on Airflow@yahoogroups.com
. Someone is bound to give you an answer.
I rebuilt a water pump on an S2 that we resored here in Australia about 12 months ago however I don't have the information regarding bearing sizes etc as the information has since been archived.
I do however remember that the bearings were over the counter items.
One word of warning though it that you should not start the engine without coolant in the cooling system as the mechanical seal in the rear of the pump requires water to lubricate it and keep it cool.
Without coolant the seal can be very quickly destroyed.
If you must start the engine remove the fan belt and only run it for a very short time so as to minimise the heat rise.
If you draw a blank on the seals and bearings I can open the archives and find the relative information for you and finally if you want to send it to Australia I will rebuild it for you and return it.
Aussie C9 Airflow Coupe