NIB - Very Likely
It's very likely the power cord was covered with rubber - not Neoprene, which is a synthetic rubber and can really last a lifetime. I've seen countless power cords that crack through aging. And yes, a rat could be afoot here, too; but based on the cracking, not likely. What the seller conveniently fails to mention is "does the darn thing work?". I know, I know: too afraid to plug it in.... Seems to me it's the outer jacket where most of the problem lies. Before I'd plop down that much $$ for it, I'd ask the seller to put on their "brave hat", or whatever - turn off the appropriate circuit breaker, plug it in, with little movement of the power cord, re-set the circuit breaker (or fuse) and see if it actually works. And then buy it, as it looks like a beauty-!