Hi Justin,
As you get deeper into the hobby you will find rats/mice are actually a fairly common design.
I think the deep symbolism in this one has already been deciphered and I'm a bit late to the thread.
What I will say is this is a decent pickup for a rookie collector! A nice cultural design, authentic piece from the Edo Period, the rat sticks out from the base which makes it "pop" which is a quality many collectors like. Hard to tell the school as others have said but if I was to hazard a guess, maybe Aizu-Shoami?
Don't quote me on that though! I'm guessing mostly based on the 3 dimensional carving of the rat, the iron base and the contrast of metals in the carvings.
Interested to see what Piers and Dale think, if they have any schools in mind.