I must admit I am not familiar with Parker at all, but there's always my buddy google. And according to google, the 1967 film Point Blank and the 1999 film Payback (with Mel Gibson) were both based on the first Parker novel: The Hunter. Cool.
Here's my take on the man with a suit and a gun (as David so eloquently phrased it.) Been down with the flu for a week, so thanks for the warm up to get back to drawing!