OEM stands for Original Equipment Manufacter, which usually refers to a part that was made by, or under licence from, the company who made the original part.
Don't confuse this with parts that are 'OEM Spec' which usually means that the part was not made by the company who made the original part, nor is it licenced by that company.. it just meets or exceeds the specifications set for that part by the original part mfg.
NOS, or 'New, Old Stock' is a term used to describe a part or component that has never been installed, and is generally old.
As mentioned earlier, this dosen't mean perfect or rust free, and dosen't even really mean it is still operable.. just that it was never 'used' or 'installed'.
New, Old Stock does not mean that the part is a OEM part, either.. it could be made by anybody.
Sounds like you want to know if your door handles are 'stock'.. meaning, what would have come on the truck when it was new.
My guess is that it would take a trained eye to tell the difference between an 'aftermarket' or 'repro' handle and a 'stock' one just my looking at it.. altho i'll bet a repro wouldn't weigh the same as an original.
