The stock 4Runner wheel uses a mag style lug nut, so you would have to find out the lug diameter, length and thread pitch of the trailer’s hub to be able to find the proper lug nut that would allow you to mount the stock wheel to the trailer. I’m sure the trailer manufacturer has a hotline you could call to confirm if the info isn’t readily available online.
Procomps use a weird extended shank lug nut. Post #8
here shows what they use, just for reference.