With that budget bayonets are your best bet honestly. The Freehand design is solid and falls right in your range. Saw a good breakdown at https://follownews.com/the-best-bayonet-knife-skin-under-500-bayonet-freehand/ that covered why it's a popular choice. Pattern looks clean and it's not oversaturated in the market so feels more unique. Take your time comparing a few options but that's probably where I'd start if I were you