A few months ago, hermes.com had both palladium and gold hippo for sale at $295. I believe the carousel costs about the same, although someone posted $280 in other threads.
Do you mean the charm locks issued each year or the standard H lock that you get with a Kelly/Birkin etc? If the standard lock I paid about 65 Euros for a new gold one so that's about 90USD or £45. I think a Palladium one would be about the same. Hermes don't sell these over the counter and have to order one for you.
thanks cynthia, Rene, Christiflora, CB, pursenality, Mscupcake and Fleurs. looks like i can get the hippo one from the website which is convenient. and i also want the elephant; it is adorable.