They are the same as YJ, or waggie's, got 1 at the pic a part for $1.00, I think the threads are 1/2-20. Lock nut, with the crimped top not nylon, Should be able to get at most hardware stores. (They used be called a Stover Nut). You can try to chase the treads on the old one.
86 CJ7 5.7 vortec. 4L60,D44's,OBA,Air tank bumpers w/D rings detroits,4.88,35" bfg, mt's 9500ti warn
86 CJ7 2.5 detroits, OBA 4.56, air tank bumpers, w/D rings,9500I warn 31x10.5x15, Trxus
86 CJ7 bone stock, w/factory 44 never seen the dirt soon to be for sale
87 Wrangler also never seen the dirt.