will they fit?? (backspacing)

I'm looking for a set of wheels for my 91 xl Explo to run until i gather everything for my SAS. As of right now she is sitting on some miss-matched tires and wheels and I want to get a cheap set that is matching but tall enough to drop my cruising rpm a ways so she isnt spinning as hard. Ive run across some stock 3rd gen explo wheels that are fairly cheap but Im not sure if the offset is too positive and will cause problems or if theyll be okay. Any help or input on other stock wheel/tire set ups thatll work are much appreciated. Thanks!