Considering the engine and near mint condition it's priced within ranges of previous Tiger sales I believe there was a similar year Duramax dually with obnoxious lift listed at $85k last year and it disappeared from sale. The tapatalk tiger forum is helpful for deeper Tiger info and a classified forum with history you can review. We paid $32k for our 2005 Chevy 2500HD 8.1/Allison 187k miles Tiger in March 2021 but I also had the luxury of a reasonable seller - but mine is higher miles and been used some (which I like - new crap gives me anxiety)
Some highlights of this Tiger:
One ton chassis on early CX (many trucks like my 2005 were 2500)
Legendary 7.3 diesel (loses novelty for me- I already have one
Excellent condition I would imagine your engine well maintained too