You can get a locking pin any where from Academy, BPS, Cabelas, Wally world or Lowes, Home Depot for that fact. The pin is plenty hard enough just get one with a good lockset. Good luck.
Edited by 97fordnut (09/29/0910:20 PM) Edit Reason: spell check isn't working
I use a mig welder and "tack both the "stinger" , and pin.(dont want a thief to pull pin and leave me pulling on a tack weld). keeps the thief away ,( they dont usually have a 3" grinder with them ) ... and no noise when not pulling.
The locking pin is a good solution if you want to tow trailers with different hitch heights. One of the problems with receiver hitchs is that thiefs can take your trailer and ball mount if you just use the pin.