Your right Phil, it is easier to shop here in Farang friendly Pattaya point taken, as I mentioned if you do get to visit there is a small Indian shop next door to the Sikh temple Soi 17 just off 2nd rd, they stock Mango powder, garam masala and sometimes the ready mixed boxes of tandoori masala along with big bags of basmati rice and cans of ghee they also stock other ingredients that are hard or expensive to come by like green and brown cardamons and Indian bay leaf , no mint though, I have seen it fresh in Foodland as well as in those small expensive jars, have you thought about drying it and grinding it yourself as it should work out a lot cheaper, also there is a similer plant available at the markets that smells and tastes a lot like mint maybe you could use it as a substitute.
Regards...........Gary