Jonnin

http://www.dnj.com/story/news/2015/02/27/swat-commander-misfires-gun-carpet-smyrna-town-hall/24144261/
 
A 25-year officer with Smyrna who has been chief for eight years, Arnold said his department has had four or five incidents involving officer guns firing by mistake. Only one of those in 1998 involved an injury to Officer Muhammad Ali (formerly known as Robert Ladell Haynes).
"He almost died," Arnold said.
The chief recalled that Ali is now on disability after being shot in the groin and losing a leg when he went to pick up a prisoner in Nashville and dropped a pistol after reaching for it in a metal box that holds weapons while lawmen are at the prison. 
 
You should be able to take it from there with his name if this is the one you recall.

If it was just the extreme tip ...
 
Do you *need* a sharp pointy tip?
If not, you can give it a screwdriver tip and use the blade to cut stuff.
If you need a sharp tip, you can cut it down to a point again and it will now be thicker, stronger than ever.
 
If it broke back too far, it may be hopeless, but you are NOW the proud owner of a ruined knife that can be abused in a tough environment without worrying that its going to ... get broken or something.   I would make it work for me and not bother to buy a new one that ... will probably get bunged up on the job.
 
That said look for a thicker blade next time.   Buck still makes thick, cheap single blade lock blade workhorses, as do other brands.   I dunno what they call the line now but ive got a 30 year old bucklite that is still going strong and Ive used it all that time, the blade is noticeably shorter than it was new from just sharpening and use over the decades.  If it was gonna break, it would have by now too, I used it as a screwdriver, pry bar, and whatever else along the way.

I forgot you were a seller.   It would be a good CYA to NOT recommend +P ammo for them in your situation.  I can't see the guns ever failing but people are idiots in general and odds are if you said it was OK someone would cram 50 boxes in one and break something (its harder on the guns, period, and in the best case it accelerates the speed of wear-out and chances of breaking things).
 
And that means you can't roll your own either.   So, um either buy some to sell if you sell ammo or mention a brand or two as I did and tell them "its out there, go figure it out for yourself".
 
I would answer the question of self defense.... "its an antique.  It will work, but its not your best choice; its more of a collector's item and target pistol.  If you really want it for self defense, you can use blah blah ammo in it but let me show you this RIA 9mm 1911...   ".