m18 R1 AMD advantage

wondering if this model is still on sale anywhere or a good place to find it. Was hoping to find anywhere other than eBay. Was also wondering about Linux support... I'm assuming since it's AMD it's probably great. I've always wanted an AMD dgpu laptop and this seems to be the most powerful one currently in existence still since there wasn't a 50 series competitor and AMD seems more focused on desktop and igpu.