Great title, thought it was about RAT-3 knives
I have one of them in Ram's Horn.
Always good to hear and see about somebody getting a new knife pattern they like
The Muskrat is an interesting pattern that takes some skill to make, especially if it is on a single-spring. Having two identical blades for skinning, so you can keep at it without breaking for sharpening, makes some sense in that context, but I've not found the need myself...However, it is an aesthetically pleasing pattern and every 'serious' enthusiast ought to have one in the collection.
Don't have a CASE version myself, but Chestnut Bone cv is always a satisfying option. For those who may have a version whose dye is weak, a good tea bath with strong tea overnight will soon bring it on
don't get appalled by the blades blackening though-you can always tape them beforehand or polish it off afterwards. Here's my Rat from Queen Cutlery, possibly one of the best made production knives I own: no gaps, play or rub, strong W&T and D2 blades on a single spring. GEC made a 66 called a Mink Skinner which is a shorter type of Muskrat and a weird Trapper called Furtaker- Clip/Wharncliffe from the same end, on I believe a 54 frame. I like the fact that GEC does experiment with blade assortments, a slap for those fogeys who mutter on about "It's never been done before, m'grandaddy wouldn't recognize it!"
The Possum Skinner 82 is another Rat offshoot type, California Clip/Wharncliffe opposite ends for those who fancy 2 different blades. My own SuperRat would be California Clip/Sheepfoot opposite ends, yet to happen in round bolster form.