Yeah that's totalled. Happened to mine just a few months ago, with less damage than that (and none to the frame). I don't have enough experience to tell you what to expect beyond that, but maybe my story is instructive.
I have a 2002, about as clean as yours, but no unicorn. Got rear ended and pushed into the vehicle in front of me. The bumper was pushed up a bit, but not bad at all.
Insurance put the value at $5500, which was close to KBB. Repair estimate was $5000, which was over the limit for MD (80%). I bought it back from them for $3500, since they deemed the salvage value at $2000.
I was able to do the repair myself for free. The damage is still evident if you look close, but it's not obvious.
In the end, I my truck is a little less pretty, I can only get liability insurance and the KBB value is about half, but for all that trouble I got a $3000 check to put in the bank.
If I were you, I'd look into getting the frame fixed in a shop if needed and doing the rest yourself. That's a real nice truck, it'd be a shame to give it up, especially considering what they'd give you for it.
This is my best guess as to how I see it playing out as well, your numbers seem higher than I expect them to be however. Little less pretty but functional is fine with me. My biggest concern with any fix will be PA safety inspections, I'll have to find out where they come down on frame repair and structural integrity.
I'll take her to a couple body/frame shops to get a few opinions before meeting with the insurance scheduled shop later in the week.
I'll keep the forum posted as it plays out. Appreciate all the opinions and advice, feel free to keep it coming.

