All b25's came with oil coolers. The 325eS and 325iS came factory with sport seats, different lip or air dam, LSD final drive and trunk spoiler. No iS or eS in sedan formats.
Gasturbine, enter the last 7 numbers of your vin into realoem.com and you will see all the options our car came with. Being older cars, they often have swapped parts.
The 1986 325es Delphin project LINK
Project 1988 325i sedan "Pinky" LINK