I'm looking to buy a 1" diameter wood dowel at least 108"(274cm) long or two dowels together that total that length. I need two of them. Where can I go in Pattaya?

Any curtain shop should have that, plenty of them around town now.

You could try the wood store (dont know the name) on Pattaya Tai, about 200 mtrs on the right, travelling from Sukhumvit road. They have a good selection of hardwood and softwood profiles.

There's a similar shop on Pattaya Nua, about 50 mtrs on the left, travelling from Sukhumvit Road.