Local to SJ FB group for used bikes and gear. https://www.facebook.com/groups/549455585096184/
DE/MD/SJ/SEPA area https://www.facebook.com/groups/1431989913773323/about/
Occasionally, things nearby will show up here too. https://www.facebook.com/groups/184012971687826/
I found a few on there but ive had no luck with people answering me backfacebook marketplace
Also....
Peep this
http://www.mtbnj.com/forum/threads/specialized-camber-29-elite-size-large.44008/
This fits the bill, (almost). May be worth checking.
The bottom bracket would be my point of contention. Never was a fan of the wedge style- creaky asf. Otherwise , looks good.
Yeah creaky is no good. I'm a big guy so they will definitely creak.
That was just my opinion. Most will agree that for single speed, rear dropout adjusting is the way to go