My #@%$ Cat Destroyed My ARC REF 5SE. Soliciting Suggestions.

Wharfy, really sorry to hear about the damage. 
I have a cat also—and guess I should take solace in that my electronics are all sealed.  I don’t like ventilation slots/holes. They are always an invitation for damage. Hope you can find an affordable way to get your music back in gear. 
As for all the cat haters on here—my cat is highly trainable and understands what we want and need. None of that is gonna help if s/he is terribly startled, which sounds like the case here.

BTW, if you weren’t home, how do you know what caused the cat’s behavior?

@drama, 
Cat pp is pretty distinctive odor-wise.
B

     Don't put down your cat. It probably does have a health problem, more than likely a urinary tract infection. The cat haters here probably haven't actually owned cats. They are often more dog like with their owners.  If you get a dog, you've gotta walk em and scoop poop. I had forgotten how much maintenance dogs are until we kept a lost one for a week before finding its owners. His barking set our alarm off twice while we were out, resulting in $125.00 in fines for false alarms.  I liked the dog but didn't miss him when he was gone.  I've owned 7 cats over the last 25 years , and only had one that went outside the box. She was 19 years old and terminally ill,and collapsed and passed and later that day. It probably killed her to know she went outside the box. I Never had trouble with cats destroying audio equipment; all have showed no interest in my turntable either.That being said, if you did have that amp repaired, any cat pee that is missed in cleaning will likely smell pretty bad when heated up. I wouldn't trust that the repaired amp would come back totally free of urine. Better to replace it in my opinion, unless they can guarantee they can get it all. 
     

Bob is correct in that a cat or dog that has always been clean, has accidents when old, REALLY feel bad and don't understand. Any scolding at all is NOT called for! CLM, cats live's matter. All 9.

Why is there a question here?  Kill the cat, without damaging its coat.  Then have your taxidermist mount it on its hind legs with its front paws positioned so as to hold your record cleaning fluid container.  Then, place it next to your audio rack facing outward as a deterrent to its successors.