Not sure where to get it locally in New England but if you want stripper clips think about a case of two of Yugo M67 ammo already on strippers (it also comes not on strippers so make sure you get the right stuff). It is corrosive but it's for a SKS, not a x39 AR. It's brass and great shooting ammo and the stripper clips are the best, not the crappy new Chinese ones that are hit or miss at best.
All you have to do is clean the gun normally after shooting and the corrosive ammo is no big deal. If it's a Yugo SKS make sure you clean out the gas valve, corrosive ammo or not. Those things are why I don't own a Yugo SKS and probably won't unless it's an older M59 without the gas valve and grenade launcher, not a M59/66 or M59/66a1.
I am not familiar with MA laws about ammo but if you have a way to get ammo shipped to you PM me and I can let you know where I have ordered M67 ammo from. Maybe a MA dealer can order it for you?
Most still ship to CT with the proper CT permission slips.