Not as many as you'd think. If we restrict the field to merely high power liquid fueled rocket engines that are potentially for sale (to be differentiated from makers of rocket engines that are an integral part of, say, a nationalized launch vehicle, and not for sale as parts) then you have: NPO Energomash, RKK Energiya, Aerojet-Rocketdyne, and maybe SpaceX.
Other than those companies, if you want a liquid fueled rocket engine with more than 100 kN of thrust then you'll have to make one for yourself or go begging to one of the vertically integrated rocket makers (Snecma makes the Ariane 5 first stage engine, China, India, and Japan have their own launchers, as do a few other countries).
Other than those companies, if you want a liquid fueled rocket engine with more than 100 kN of thrust then you'll have to make one for yourself or go begging to one of the vertically integrated rocket makers (Snecma makes the Ariane 5 first stage engine, China, India, and Japan have their own launchers, as do a few other countries).