Columbus do a 1" carbon fork, Ceeway do them at a good price - check if it comes with a bung (can't use star nuts on carbon). Almost no-one does 1" ahead stems anymore, because you can use a 1 1/8" stem with a shim on a 1" fork, so why make a specific one for the three people who want them? Sometimes you can get one on ebay. Miche do a perfectly serviceable 1" threadless headset for £30ish. You can convert a threaded headset to threadless by striping out the threads. Don't forget some carbon assembly paste before clamping up the stem.
(I know all this because I just built a bike with a 1" threadless carbon fork)