American Standard, Gerber and Kohler have them.
I've found the American Standard to be the easiest to find. These models use the Flushmate pressure assist in the tank.

: I am searching for a wall outlet toilet . The toilet must be floor mounted not a wall mount. I have found a couple options from American Standard, but I am having no luck with any other manufacturers. A "modern" style/looking toilet is desired but at this point, I'll take any suggestions. Any help is greatly appreciated, thanks!

: From,
: without a toilet in LA

• Flushmate web site