No other US service flies them. The Brits the Spanish Navy and the Italian Navy also fly them, IIRC. The Brits have two versions, the GR.5/7/9 land based ground attack version (much like the USMC Harriers) and the Sea Harrier FA.2, which is more of an air-to-air fleet defense fighter.
Thailand has purchased around 8 ex Spanish AV-8s for their mini-carriers,while India has around British built 16 Sea Harrier MK-51s,which are being upgraded with a new Israeli radar & BVR-AAMs.The Brits will probably retire the Sea Harrier FA2s by 2006 to cut costs,which may then be offered to India.