Therein lies the issue, at least to get a new one... The 11711 was NP3 coated and came with the collapsible stock and extended mag. That shouldn't have really been released to us civvies in this config. From what I understand, they were brought over to try to garner police and military contracts and the leftovers were then sold on the open market. They weren't that much more than the regular M4 but in very short time, the demand sky-rocketed but no more would be made. They had started importing Cerakoted ones in a 922r compliant configuration which then people could modify. Robar closed, and some other NP3 applicator companies have mostly stopped doing small parts so it has gotten harder (but not impossible) to get the small pieces done now.
I bought my 11711 new unfired and that is how it will remain. I had originally got it to shoot, but the value shot up so fast, that I decided it was money well spent to get another M4 to use and keep the other NIB. The last couple 11711's that I've seen for sale before COVID were $4,500 and I saw one sell during COVID go for ~$8,000, but people got stupid during that time on what they paid for stuff so I don't consider that an indicator of real value.