canvasback, my eyes, misty while reading this whole thread, spilled into tears after reading the little poem you posted.
Mark, it sounds like you had a great hunter and wonderful friend. Like many here I sure know how that feels, and likewise know how it feels when they've left. That rock that's ripping through your gut will get smaller in time.
Don't even bother thinking about other dogs right now. But the time will come when another one comes to your call. He/She may not be Moose, but don't be surprised when you find that dog bringing a smile to your heart.