If legal for you to purchase and own (important, these are different distinctions), an automatic knife would be the safest for one handed operation. Anything from the Kershaw Launch line will be bulletproof and have decent steel.
Non-auto non-assisted button locks (the type of knife you asked for) are kind of niche. Kizer makes some decent ones, and Civivi makes the exact razor blade utility knife you’re looking for, but in higher quality and within your budget.
Otherwise I gotta say, if you’re not a current knife enthusiast, look for sales on Benchmade Griptilians (or mini-griptilians). The Axis lock is not exactly a button press but if you want higher quality, it’s a good option.
jordanlund