Concerning the value of collectable ceramic figurines?

I've unintentionally acquired fifty three Memories of Yesterday ceramic figurines. I want to sell them. After several hours of trying to determine what they're worth, I'm still having trouble. I noticed that some figurines, that are otherwise identical, have various stamped letters, and printed information on their undersides. I don't know what they signify. If anyone that's reading this can provide information or a useful suggestion, I'd appreciate it.