Looking for these mods...

[asskicker_ak 0]

Air refuel mod or choper search and rescue mod...

 

which included in YAP, but I couldn't found the download of YAP and haven't $$$ to pay for it...

[Jarink 1]

As far as I know, the KC-135 is currently only available in YAP. Same goes for the Jolly Green. There are a couple of other tankers available (KC-130, A-310), but there is no actual way to perform aerial refuelling, even in YAP. I't there for the atmosphere and eye candy rather than being functional.