if i were to choose one, the Standard brand would be the one i would pick.
the first one has an M10x1 thread. that is metric, and why it is listed in the description.
do you have a link for your van ? "Dodge B300 van ??? engine oil pressure switch - enter [i forget the year of your van and engine size. 360/5.9 ?]
did you post a picture of your original switch ?
i have a couple of Standard Products master catalogs. if you refresh my mind with the year and engine size, i'll look up what the replacement sender should be.