Hi Clem,
Do yourself, and the next person to work on that axle a favor by buying or borrowing the correct socket to remove/reinstall the bearing retainer nuts. Yes, other tools like punches will work, but you do run the risk of damaging the nut or the axle tube threads. The person who serviced the axles previously on my truck used a chisel.
Not a pretty site when I went in there the first time to service the bearings.
As Jerry mentioned, you can get them at the larger chains like NAPA.
They are also all over the online auction sites, too. There are different types, so the trick is trying to determine the correct one for your application. Perhaps someone on this site has one that is known to work, and can provide the model number.
Best Regards...
