Sowerbutt's Mission

The Brigadier said: “My masters are concerned about a couple of unpleasant gentlemen from the old firm who have holed up somewhere in Spain. Swiss bank accounts full of Jewish gold, plenty of plunder and suitcases full of secrets. Would you keep an eye out for them?" 
https://www.amazon.com/Colour-Red-Deal-Sowerbutt-Novels-ebook/dp/B00RL9FGKM?