“Talk is cheap” is an old saying; the second part of “money buys (the) whisk(e)y” is a modern addition. The saying appears to come from South Africa, where “talk is cheap but money buys the whiskey” was described in 1955 as “a slang expression here.”

The saying is also used in the United States. In December 2011, one of the football coaches in the New York Giants against New York Jets rivalry said, “That’s the old saying, ‘Talk is cheap, money buys whiskey.’”
 
 
Google Books
Reports service: Central & Southern Africa series
American Universities Field Staff
Volumes 4-6
1955
Pg. II:
EXAMPLES OF CASH OR COLOR
There is a slang expression here that “talk is cheap but money buys the whiskey.”
   
Google Books
Afrikaanse spreekwoorde en uitdrukkings met die Engelse ekwivalent
By Matthys Stefanus Benjamin Kritzinger and N. G. Sabbagha
Pretoria: J.L. van Schaik
1981
Pg. 101:
Praat is nie belangrik nie, maar die doen van ‘n saak: Talk is cheap, but money buys the whisky.
 
Google News Archive
24 May 1984, Windsor (Ontario) Star, “Is a new arena on Windsor’s horizon?” by Doug Williamson, pg. A1, col. 4:
“Talk is cheap, money buys whisky. As for any great big major deal for them. I can’t see us being able to afford it at this time,” Rossini said Wednesday.
   
Google Books
Servants of Power:
The role of English-speaking churches in South Africa, 1903-1930:
Toward a critical theology via an historical analysis of the Anglican and Methodist churches
By James R. Cochrane
Johannesburg: Ravan Press
1987
Pg. 43:
“Talk is cheap, but money buys the whiskey”, notes Hermann Giliomee in reviewing Dan O’Meara’s study of Afrikaner nationalism, which he regards as demonstrating the need to “concentrate less on ideological and ethnic divisions and give proper weight to the important class forces that are influencing the situation.”
 
30 April 1999, Daytona Beach (FL) News-Journal, “Dispute with rabbi continuedtocourts” by Claudia Moscoso, pg. 1C:
“Seeing is believing, talk is cheap, and money buys whiskey.”
     
Google Books
Equality and non-discrimination in South Africa:
The political economy of law and law making
By Shadrack B. O. Gutto
Claremont, CA: New Africa Books
2001
Pg. 67:
As the saying goes: Talk is cheap; money buys the whiskey.
 
ESPN New York
Updated: December 22, 2011, 11:30 AM ET
Giants, Jets have plenty to say
By Ohm Youngmisuk and Rich Cimini
EAST RUTHERFORD and FLORHAM PARK, N.J.—The war of words between the New York Jets and New York Giants continued on Wednesday as Rex Ryan’s comments about the Jets being the better team continues to fuel the cross-town rivalry.
 
“I just say, regardless of the talk, it will be decided at one o’clock Saturday afternoon,” Giants coach Tom Coughlin said in his Wednesday press conference. “Regardless of what is said. Talk is cheap, play the game. That is the way I’ve always believed.”
 
Coughlin was repeating one of his longtime mantras. But, of course, Ryan responded.
 
“That’s the old saying, ‘Talk is cheap, money buys whiskey,’” Ryan said at Jets practice