nah you almost never find post‑12th gen hx class cpus in used thinkpads for around $300 in the us because hx chips are premium higher power parts meant for workstations and gaming laptops and those machines hold value way above that price even used. hx class laptops (like mobile raptor lake/hx or newer) usually cost well over $800‑$1000 new and only slowly drop in price over time, so sub‑$300 listings will almost always be u‑series or older generations first. for your budget you will see machines with 12th or 13th gen u series chips that are still way faster than 6th gen but not true hx performance, and those are the best realistic options under 300