Welcome, spanky.
If you really want an understanding of these bikes on
any level, read the information available
here. You can also learn how others have solved pump problems
here.
Should I immediately assume . . . without the in depth understanding of how all of these systems function on a micro level.
Andy
My approach is to avoid making assumptions when I know little about a subject, and even if I think I do know a little about it. Failing seals, pump removal, a bad head gasket all can allow the mingling of fluid, depending upon where you found the "little bit of coolant" in the oil.
How many miles on the bike and how long have you been riding it, spanky?