There is no budget. How good are the molle adapters that the military issued? Do the more expensive knives stand up longer to abuse?
To answer the last question, maybe, if they're designed for it. As an example, the swamp rat mega ratweiler or mega ratmandu are two knives offered by Busse Combat that will be far tougher than the kabar and cost more. They're also pretty heavy and "cost more" is much, much more. You would have a pretty tough time destroying the knives though, even if you went out with the intention of trying to break them. You could damage the edge but it would be pretty challenging to do irreparable damage.
I prefer the standard ratweiler or ratmandu thicknesses, personally, but they're only available on the 2nd-hand market now. The ratweiler being one of my favorite hard use knives in a "small" package.
Actually, since you mention self defense, the Team Gemini Ultra Light Brigade from Busse might be the best option they have currently available as it uses thinner blade stock, has big guards, cuts better, and is still nearly bullet proof. Probably my 2nd favorite Busse I've ever handled.
https://www.bussecombat.com/busse-team-gemini-ultra-light-brigade-coated/
From left to right: swamp rat ratmandu, Busse Team Gemini Ultra Light Brigade, swamp rat ratweiler (0.25" Sr101 steel), swamp rat infi ratweiler (0.2" infi steel), Busse forsaken steel heart, Scrapyard Knife Co (SYKCO) 1311.
These are just a few more examples of knives tougher than the kabar that will cost more. Again, there are a lot of choices out there and I think doing some reading and watching will help you decide... or confuse you further since we'll throw a lot of suggestions at you.
Still, bang for the buck, the kabar is hard to beat.