It’s not the knock off you think it is.
Ontario is one of the makers of the “Marine” knife and has been for years.
They weren’t just made by KaBar.
The standard model (same blade) still has an NSN.
Personally, the blade is a bit thin for my tastes. I’ve broken a KaBar before, same as many soldiers over the years.
The 225Q “Quartermaster” knife of the same vintage (WWII) is a bit better than the Marine knife, in my experience. Same opinion was held by many soldiers back in the Pacific, they scrounged to get the 225Q knives when they could. They were commonly called ‘Commando’ knives. One of the reasons they were popular is that they held up better to the prying and didn’t break like the KaBar’s when opening crates and such, typical soldier abuse.
They are out there, and depending on condition can be reasonably priced or offensively priced.
Ontario is making a new but fairly close copy of the “Q” knife and it’s for sale for $150 on the Ontario website.