The bolt handle on the one for sale is so badly rusted, it looks like it was raised from the bottom of the Ocean along with artifacts from the Titanic.
Receiver/barrel looks not much better. Maybe it's just a bad pic. I've PMed the seller asking for better pics but from the pic available, the condition appears to be 'poor'.
The picture of the 256 is a bit old. The scope, rings, etc have all been replaced on that first Newton rifle since that picture was taken. The grip cap is fully adjustable and just needs to be tightened up. The sights were removed and cheek piece installed when my great grandfather's eye sight went south. The Cheek piece was orderable directly from Newton for $3.30 including war tax. That rifle is nearly 100 years old and has been hunted hard and frequently by my family. This October it was on stand for Elk in heavy rain and was beating thick bush tracking a whitetail it put a hole through. It's certainly not any kind of museum piece.
Every single photo in every old book of Newtons seems to have the double set trigger, even the lever bolt rifle. Looking at the Newton price list and build to order options, a single trigger was never an option. When looking closely at the picture that's posted for sale, you can see the hole for the rear set in the top of the trigger guard....
Since it seems the trigger is broken or missing, that would seem to reduce the condition to 'very poor' in my opinion...