Had this problem years ago, when it was just Bitcoin miners grabbing up cards. I ended up getting a cheaper card, which was a disappointment, but has kept me going ever since. Now it's miners (again), Sony, Microsoft, and Covid. You're gonna have to wait a while if you're picky like I am.
... the only other option is to buy a 5-6 thousand dollar prebuilt PC....
If your "only other option" with pre-builts is 5-6k you are looking in the wrong places! Try a solid gaming builder like Origin or Xidax (nothing owned by Dell or HP) and you can get an awesome machine for half that, easily.
Never buy the latest or top of the line, but target the optimal price for performance. You'll save 60% or more in costs for only a 10% or 20% hit in overall performance. If there's any game today you can't max out, wait a year or two and buy a better card out of some of that 60% you saved, and you'll still be ahead. Unfortunately, this is exactly what the miners do, so you're even more in competition with them, but hopefully the builders have better supply access.
And that cheaper card that I settled for 5 years ago, installed into my 12 year old machine, is plenty for Elite.