have (oneself) (something)
To enjoy or indulge in something. I'm going to sit down in the shade and have myself a cold glass of lemonade.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
have oneself something
to get, have, or take something. I'll have myself some of that coconut cream pie, if you don't mind. You just go and have yourself a nice, long nap.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
Enjoy something, as in Be sure to have yourself a good nap, or They were having themselves a great time at the fair. The oneself in this colloquial expression adds emphasis to the verb have.
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.