Can I create such a Hive community?

Not yet. But you will be able... soon.

Quoting from @ roadscape, the man behind Hivemind and Hive communities (quote from 17 days ago):

Type 2 ("journal") is almost ready.

If you didn't understand anything, that's ok. Type 2 means a community where

• guests may comment, but may not post
• members may post or comment

A type 3 (or "council") community will be where

• guests may only read content (so no posting and no commenting from "outsiders")
• members may post or comment

You can read more about them here, but it's a little technical.

Important thing to remember is that other types of communities are on their way. Like the "journal" or "council" types described above, but they will not be the only ones, according to @ roadscape.

More from @ roadscape:

We'll have new community types which restrict who can post, but I don't think we can have it be editable at will. At least not initially. There are edge cases to consider for the backend, and the goal is to keep the protocol dead simple (and efficient) for now.

That means that once you will create a community, the type you will select will be the type of the community, you won't be able to change it or switch between them. "At least not initially".