"I wanted to buy a half a rabbit, but the butcher…

A “hare”/“hair” pun was published in Family Weekly magazine in November 1976:

A woman who lived alone had an urge to cook a rabbit stew when she saw a rabbit displayed in a butchershop window. Since the rabbit was too large for one person, she asked the butcher if she could buy just half of it.
“I’m sorry,” he replied. “We don’t split hares.”

“May I buy half a rabbit?”/“No, we don’t split hares!” is a popular version of the joke that was posted on Twitter on July 29, 2009. The rabbit joke is sometimes included in joke collections about the Easter bunny.

14 November 1976, Austin (TX) American-Statesman, “Quips & Quotes” by Richard Armour, Family Weekly, pg. 39, col. 4:
A woman who lived alone had an urge to cook a rabbit stew when she saw a rabbit displayed in a butchershop window. Since the rabbit was too large for one person, she asked the butcher if she could buy just half of it.

“I’m sorry,” he replied. “We don’t split hares.”
—Conrad Fiorello

Google Books
The Reader’s Digest
Volume 109
1976
Pg. 108:
A woman who lived alone had an urge to cook a rabbit stew when she saw a rabbit displayed in a butchershop window. Since the rabbit was too large for one person, however, she asked the butcher if she could buy just half of it.

“I’m sorry,” he replied. “We don’t split hares.” —Angle Papadakii

Google Groups: alt.humor.puns
Puns of the Weak 4/20/01
Stan Kegel
4/21/01
(...)
What did the butcher reply when a lady asked if she could by half a rabbit?
“No! I donąt want to split hares.” (James D. Ertner)

Google Groups: alt.humor.puns
Puns of the Weak: 03/01/02
Stan Kegel
3/1/02
(...)
Customer: “Can I purchase half a rabbit?”
Butcher: “No! We don’t split hares.” (Lederer & Ertner)

Google Groups: alt.humor.puns
Puns of the Weak 10/11/02
Stan Kegel
10/11/02
(...)
I wanted to buy a half a rabbit, but the butcher didn’t want to split hares. (Carol’s Humor)

Twitter
Sneha Singh Cataria‏
@SnehaKataria
I wanted to buy a half a rabbit, but the butcher didn’t want to split hares…Ouch! *tries to laugh*..
11:30 AM - 4 Jun 2009

Twitter
Bollywood Sargam‏
@bollywoodsargam
Rabbit jokes - 8194 Joke: May I buy half a rabbit?
No, we don’t split hares! .... http://bit.ly/LJ5Qo
7:05 PM - 29 Jul 2009

Twitter
EasterJokes‏
@EasterJokes
Q: May I buy half a rabbit?
A: No, we don’t split hares! Happy Easter Jokes
6:57 PM - 8 Apr 2012

“I wanted to buy a half a rabbit, but the butcher didn’t want to split hares”