I had the .450 NE Elephant. I bought used, but excellent, with nice but not spectacular walnut.
I paid $1800 in 2014, it included a die set and 60 pieces of new brass. (Dies and brass were worth an easy $200 in a Nitro Express cartridge.)
I sold it to a friend in 2016 for what I paid. He really lusted over it and I had had my fun.
NIB with superb walnut I don't think I would go less than $2000.
These are awesome rifles, liked the slightly matte bluing and the Express style sight (all No. 1s should come with the express sight over the dinky flip sight.) Warne rings were nice too.