It depends. They are really hard to get. Eggs are often easier to get, but raising the cuttle for the first month or two can be really expensive - food costs! So, a baby may go for 20-50 bucks, same with a one or two month old.
I have plenty of empty tanks here. However, I've read the articles and yet I have NEVER seen a cuttlefish or eggs offered anywhere on any list I have ever seen in 7 years. Octopus yes. Even blue rings occasionally. But never cuttlefish.
I wouldn't have the foggiest where to actually get one.
They don't show up on lists as cuttlefish eggs, but are listed either as squid eggs or octo eggs so you just kind of have to know about them. Sadly, many wholesalers get them and feed them to other fish. Most LFS wont touch them. Besides that, they simply aren't imported all that much.
I have been trying to make them more available, but it is a small market, and I am much more interested in making captive bred animals available than furthering the trade in wc animals.