Oil Pressure Light Problem

I have a 99 Spyder GST. The oil pressure light seems to come on every time I stop at a red light. I recently had an oil change and have even added oil. I was thinking I need to replace the pressure sender. However I see there's two parts, one for the gauge and one for the light. Can anyone advise me which part I would need or if I'm totally wrong what I would need to fix this problem.

Thanks.

youll need the pressure switch, located on the engine...  the smaller one, which is for the light.

the larger one is the pressure sender, the smaller one is the pressure switch.