I’m in the south and would like to buy a mask and snorkel, possibly fins.

I’m in Chumphon, no luck finding decent gear here.

I’ll be headed for Hat Yai soon, can anyone recommend a place to buy snorkeling gear there?

Chumphon.....Did you ask Werner already?

http://www.divechumphon.com/Scuba-Diving-Chumphon.html

I think he has very limited stock, but can get everything out of Phuket at a good price.

If I recall right, he had excellent masks at excellent price 1-2 years ago. But that might have changed