Did you ever find a pump? I got a used one from Suprman a couple of years ago for the Cat 3116 in my LMTV (M1081). It's been kept out of the weather since then, still dirty but I never installed it on my truck. $100 includes shipping. You need to make sure that the pump you need is the same, I don't see what model and year your truck is, or which motor you have. The pump I have is a Sunstrand A17L34011, Date 96 K 01
BTW, I've still got a small leak, but not from the pump itself, it's from the connections on top of the pump, the line coming from the reservoir. There's a couple of seals on that that could be bad, or just loose connections. Try tightening those first, though they're hard to get a wrench on.