NASA has somewhat larger versions linked on this article, though they aren't really sufficient for larger wallpapers or prints:

https://www.nasa.gov/centers/armstrong/features/supersonic-s...

The photos aren't yet listed in their image database[0], unfortunately. They also publish[1] high-resolution versions on Flickr, so it's possible the photos might make their way there in the near future. Alternatively, they give a phone number (202-358-1900) to inquire about media use of specific images.[2] Maybe I'll give them a call later if someone doesn't beat me to it. Or the high-res photos will make their way onto Flickr, since they already posted to Instagram as of yesteray.

0. https://nasasearch.nasa.gov/search/images?affiliate=nasa&que...

1. https://www.flickr.com/photos/nasahqphoto/

2. https://www.nasa.gov/multimedia/guidelines/index.html

I came here to ask this!