My mom did it for about 10 years and had generally good results. I tried it and found the lenses too uncomfortable to wear. Soft contacts don't bother me; just rigid ones.
Give it a shot! The worst possible outcome would be no change.
I take it that you would need to go to a specialist? I know nothing about eye doctors but are there special ortho-k providers that only do that type of treatment or would it fall under a normal optometrist? I guess the top dog of the eye care totem pole would be an ophthalmologist.
Personally, I'd always go to a specialist for anything that involves messing with my eyes. I don't know specifically if there are ortho-k specialists, though.
And, no clue on the cost. I tried this out about 14 years ago.
Give it a shot! The worst possible outcome would be no change.