Can you give an example of a particular item type, size and cost?
The circular wall-hangings often come in multiple panels so makes transport reasonable.
The best shop in Baan Tawai, for your item, might be easier to narrow down if we know the item type. You could spend an entire day there. Or ask the restaurant owner which shop(s) they recommend.
One recommendation might be Benjarong (five colors), hand-painted pottery. Finding a "real" piece may be challenging. The best work is done in family-owned/operated studios. You can visit some of these. During a tour of Samut Songkhram province, we visited Pinsuwan Benjarong. Samut Songkram is worth a one or two day visit, IMO, maybe with a rental making your way down to Hua Hin?