Okay, what other monsters can you get them from apart from the ginat sea snake and other high level monster? Ty in advance :P

I believe this is what your looking for.

 

 

 

Could always just check the bestiary as well.

you could get them easily from rock crabs something like lvl 20 to 40

You can search the Tip.It Bestiary with the key word of 'pearl' (don't use 'pearls').

 

 

 

Dagannoths drop a decent amount of oysters if you can kill them. Besides that you'll have to go to the Sea Snakes or Rock Crabs. I don't believe Rock Crabs provide a good amount though.