Which place are you from ? You can look at export surplus garments . You get all brands and probably the sizes you are looking for , you might get much more variety since not many are that tall or have such requirements .
Mostly, it is the women and girls who keep debating on bra and cup sizes or panties .. this is a welcome change
I too fit in the same boat and need reccs for some big ass shoes (Uk12 and above) with proper wide toeboxes (barefeet kind also welcome) . As for clothing, I make do with h&m somehow but they don’t keep the size in stock and recently I feel like I’m going to break the limit of 2xl, so need reccs for that too. Height is around 6’3” ish