In 1982 I paid $140 for a Randall Model 14. That's a bit over $300 in today's dollars. I was overjoyed to get it, but soon learned it really wasn't all that good and eventually sold it off to cover another purchase. So far that has been the single most expensive knife expense I've ever made.
I have little doubt that some day I'll top that, perhaps some day soon. Compared to a firearm purchase three hundred bucks really isn't all that much and I've seen any number of working blades by custom makers that are priced well over $300 and worth the asking price.