James Hadley Chase - Have This One On Me

Published by Corgi (ISBN: 0552113093) in 1986.

Back cover blurb: "Alec Worthington, the C.I.A. man in Prague, has suddenly found the climate disagreeable. He wants out.

The C.I.A., not unused to this kind of problem, decide the best way is in a box...but then the real problems begin.

How to find a replacement and settle him into the job without attracting suspicion? The answer is a decoy, a dispensable agent. Someone like Mark Girland, a man with a fatal weakness for money and women. A man known to the Russians, and a man the C.I.A. would be only too willing to lose. But Girland has another basic instinct... the will to survive."