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

Circuit boards can be repaired,  parts on the board can be replaced,  If it were mine,  I'd give it a try.  I realize everyone can't do this .  A few years ago I decided to dive in and truly learn about power amps, I've been purchasing old amps, rebuilding and repairing them.  I purchased a used Oscilloscope and haven't looked back. I think its worth the try. 
You need to find which circuit was shorted out by urine,  do a serious cleaning job there and start with verifying which parts are bad and if a circuit trace is damaged.  Good Luck,  Tim

Judging by the number of "cat lovers" here... I'd make "lemonade from lemons."

First open the cat's "go fund me account" - "SAVE THE KITTY."

Post the cat's YouTube video of the cat in a cage with a subtitle that the cat has one week to live, before its executed, unless other "cat lovers" "bail" it out of "death row," referring the viewers to the cat's "go fund me account" - "SAVE THE KITTY."  

You'll have the funds for a really nice replacement of your Ref 5SE in a few days!

Hell... I'll sell you mine for $10,000 (just like new)! 

"SAVE THE KITTY!"

Maybe replace the ARC with a CAT. I bet the unit is worth at least $500.

"Homeowners insurance doesn't cover repair or replacement because owning a pet means you assume liability/responsibility."      Makes sense!     After all,  whose fault is it, that you have a, "#@%$ cat" (your own description) in your house?          

That is very bad luck. Repair should be possible though, but finding the right person to do it will be difficult. Have you considered replacing it, even temporarily, with something different while waiting for a used one at the right price.

I use a DIY valve preamp which I quickly threw together to see if it was what I hoped it would be, intending to do a more serious build when time allowed. This pre with only mediocre parts outperformed my expectations but from long storage had developed a hum.

Not having the time to rebuild the way I would like I chose, after much research, a unit from Ed Schilling of the Hornshoppe called 'The Truth'  It is solid state, nothing to look at and has no gain, but is simply amazing and I doubt now if I will bother to rebuild my valve amp. Retail about $1300 because I asked for upgraded OCC input wiring and a remote.

A long and entertaining review of this by Arthur Salvatore:http://www.high-endaudio.com/RC-Linestages.html