A family run company (I'm pretty sure it's 5 generation) and owner of Wachusett Mountain ski resort, Polar Company has a factory just down the street from HC. They make the best seltzer drinks and I always have my eyes peeled for them at grocery stores, CVS stores and Targets in Massachusetts. I'm not sure how far they distribute, so I can't say I look for their drinks in many places outside of New England and New York. They brew ale and flavored ale, which I have never tasted but am sure they are tastey, for those who are 21+.
They even sell beer taps from their company's website-->>
They supposedly sell variety packs of different flavors in cans which I have yet to find anywhere. And here is a colorful video from Youtube that displays their many flavors.
*I'm currently gulping down some of the diet Raspberry Lime 2 Liter bottle.