Check out sockdreams! They have some great thigh high socks that come up halfway on MY thighs (I’m 6’4”) and they’re very comfy. If the socks are having trouble staying up, you can get some garters like another comment suggested. I got my garters through sockdreams as well.

If you want more fem clothes, I get a lot of my stuff from Torrid. Decent quality for the price, and they have a lot of clearance stuff which helps a lot with the cost. I have some really well fitting jeans from Abercrombie and Fitch, too. Plus size stuff is a safer bet since it often has long/tall options.

Best of luck!

SockDreams.com stocks tube socks (good for larger feet) and extra long socks (good for large/long legs). They also have a lot of pride designs! Their physical shop is in Portland, OR, USA.

Edit: don't forget to buy sock glue

Unfortunately I'm a little shorter than you also with thick thighs and i've had litrle luck with thigh high socks. The best I've found are sockdreams.com, but even those roll down my thighs after a while. I wish you much luck in your journey discovering yourself! <3

Everyone else seems to be on the same page with that site, I've never heard but definitely also checking it out, but my main advice is definitely order bigger. My dumb ass knowing I'm big even for male sizes still ordered female L and expected to fit. (it technically does, but is at the elastic's limit)

Also don't buy online while frustratedly drunk.

Also, it can be wonderfully helpful to take your measurements! You can measure hip, bust, inseam, etc, by looping a piece of string around your body and then measuring it. Most clothing brands have size charts that let you match your measurements to their size rules. Remember that just because you’re a size 20 in one brand doesn’t mean you’ll be a size 20 in another, always check the size charts.

Before I started my journey of self discovery, one of my favorite pair of socks are some (unfortunately male style) knee-high socks. Been slowly been coming to the realization that it was because they made me think that it was similar to how stockings felt. I even called them my stockings for the past year. Wore them under my jeans all the time at work, and if anyone saw them, it wouldn't even turn heads.

If you buy panty hoses, look on the back. Every brand is a bit different. You can first buy cheaper ones to try out, say 15 eur instead of 60. Afaik it will basically always fit, it's just that the height will be different. Also there's a lot of difference in stretchiness. Also it helps to wear socks inside so your toe nails don't do a number on them.