A better use for fresh oysters, in my opinion, is in Haemul pajeon (해물파전), a thick pancake full of green onions and various seafood.
Busan's Dongrae Halmae Pajeon is the place to go for this delicious dish. It is an institution in Busan, and was a favorite spot for the late South Korean dictator, Park Chung Hee.
If you do go there, you might have a bowl of eel soup (Chu-eo tang 추어탕) as well, it is delicious and distinct from other provinces' versions.
The address in Korean is
부산광역시 동래구 복천동 367-2 367-2
It's not particularly easy to find, so it's probably best to take a taxi.