$10 for solid colors purchased pre-arrival, but MagicBands are getting hit particularly bad with supply chain issues. Stock has been awful at both MyDisneyExperience.com and ShopDisney.com.
If you have any old bands, those should still work.
The selection on MDE for MagicBands for Disney resort guests and APs is pretty limited, currently seeming to be anywhere between 15 and 35 options. Right this minute the only solid color choice is blush pink.
Keep checking, if you have a while before your trip, since the selection changes often.
I got a Dark Purple one a couple of weeks ago. I was holding out for the new plus ones but grabbed the purple one when it came up for DD. DH & I are using our bands from our Oct 2020 trip
I'm really surprised that the 50th anniversary bands aren't more popular. They've been pretty consistently in-stock since they were released and I think they're some of the nicest looking bands they've ever put out, complete with a metal slider.