You should use a thermostat that is specific for your car, rather than just a generic one. I am not familiar with your exact car, but a lot of thermostat have two sealing surfaces, one to seal a passage in the block and one for the main water flow (The one that Diegomx listed is one of these). Some thermostats have two flow valves, one small one that opens early, and one larger one that opens later.
1991 MX6 Turbo 4WS back on the road again after 5 years.
1990 4WD Capella Wagon2.0 FE3 now tin cans.
1988 4WD Capella Hatch 2.0 FE3 DD