The water pump attaches to a flat metal plate that covers the timing chain. Is there a gasket under the plate that seals engine oil ?

 

Yes

 

This is the gasket set for my 1983 Ninety-Eight.


The gasket on the right with the two holes is the one you need. I don't know if those are available individually, but the kit is cheap so grab one. That way, you'll have an extra water pump gasket. You get two in the kit. One is for A/C and the other is for NON-A/C equipped cars. Also included in that is are the fuel pump gasket, front crank seal, and front oil-pan seal. Fel-pro should make the same kit. Should be easy to find at a parts store.