Spline drive wheel nuts are wheel nuts that are basically a wheel nut that takes the shape of a gear as an example. Most are 6 to 8 teeth persay. Often used as lock nuts as well as they do require a special socket but keep in mind unlike wheel lock keys where it is rare that someone may have the same lock key the spline drive socket should fit any spline drive with the same number and teeth / gear shape.
I'm assuming these are used wheels otherwise I would suggest getting your wheels elsewhere if they can't provide you with the proper lugs. I did get my splined lugs for my cars wheels from the local Advance Auto. I want to say they are made by Dorman.
A splined lug nut serves two purposes , looks and as a locking anti theft device . You need a special " key " for each of them . They should work on any wheel just as long as the thread of the nut matches the wheel stud along with the correct length .
generally its only the seat needs to be right, but as noted the bore to the seat can be smaller. on my cheap but decent Drag brand wheels i needed to make the socket a little less fat + as a friend showed me to put the socket connected to a spinning drill while grinding it.