Not an expert, in anything, but I have been forging, not checks, for 30+
years. A 225 lb anvil around here would bring 2 to 3 dollars/pound.
If you have a ball bearing do a drop test and see how high it rebounds,
just drop from about 18 inches. If it rebounds 70% or more it is probably
a good anvil.
Use a carpenters level or square to check the flatness of the work surface
(face), check length wise as well as side to side. You don't want to much
sway back, a little won't hurt.
As far as the anvil ringing, some will some will not. A cheap cast iron
anvil will ring like a bell but the first time you hit it with a 3 pound hammer it will probably crack or chip.
From what I can see on your pics it has some chipping on the edges,
but, not something that can't be worked around.
Final opinion, buy it. Then go to a used book store and buy a couple
books on blacksmithing. What kind of forge are you thinking?