The Big Show Act I: The Prince and the Wrestlers (2009)

From publisher blurb:

The heroes arrive at the rendezvous point (feel free to use your favorite spot), where they meet The Limey, their current handler. He takes possession of Wang Bao Li and hands him off to a couple of his plainclothes compatriots, then settles up.
For bringing back the scientist, he offers $1000, American. He offers to double the reward on this mission if the heroes agree to undertake another one for him.
It seems one of their operatives, codenamed Blackjack, disappeared while delivering a diplomatic pouch to a Greek operative on Olympus, a Greek colony world near the Geneva system. They have confirmed that the Greek operative never received the pouch, and was subsequently killed during an operation on Geneva. Though the British Star Empire is on friendly diplomatic terms with Greece, they do not want to break certain protocols by sending agents directly in their employ. Providing a small ship (if necessary) and modest finances, the Limey asks the heroes to find the diplomatic pouch, and the fate of Blackjack.

The direct rewards modest (about enough to keep the heroes flying for another year), but indirectly, the Special Service handler hints that additional employment is always available to trustworthy operators.