Since the person isn't adding unsolds ( http://backpack.tf/vote/id/554a2287b98d8841718b456d ), I guess I have to do this

Unsolds

14 ref | 3 days | http://www.tf2outpost.com/trade/25860002

14 ref | 6 days | http://www.tf2outpost.com/trade/25831491

0.85 keys | 3 days | http://www.tf2outpost.com/trade/25858527

0.85 keys | 1 week | http://www.tf2outpost.com/trade/25779261

0.85 keys | 2 weeks | http://www.tf2outpost.com/trade/25759389

1 key | 2 days | http://www.tf2outpost.com/trade/25867093

1 key | 2 weeks | http://www.tf2outpost.com/trade/25720634

1 key | 2 weeks | http://www.tf2outpost.com/trade/25720315

1 key | 6 days | http://www.tf2outpost.com/trade/25833646

1 key | 1 month | http://www.tf2outpost.com/trade/25561739

1 key | 4 days | http://www.tf2outpost.com/trade/25845762

1 key | 3 weeks | http://www.tf2outpost.com/trade/25667117

Sellers (from Good Shiz's suggestion)

13 ref | http://www.tf2outpost.com/trade/25878375

13 ref | http://www.tf2outpost.com/trade/25877373 (poorly bumped, but has some amount of views, should be passable in a way)

One 12 ref seller as well, but way too young

There are people selling at 12, even 11 refined. However those trades are young and will probably quicksell, and it appears 13 ref is a stable price for this item when other one of the 13 ref sellers now sold and didn't take a lot of time.

Updating the proof

Unsolds

14 ref | 3 days | http://www.tf2outpost.com/trade/25860002 | Sold but took 4 days

14 ref | 1 week | http://www.tf2outpost.com/trade/25831491 | Still unsold

0.85 keys | 6 days | http://www.tf2outpost.com/trade/25858527 | Still unsold

0.85 keys | 2 week | http://www.tf2outpost.com/trade/25779261 | Still unsold

0.85 keys | 2 weeks | http://www.tf2outpost.com/trade/25759389 | Still unsold

1 key | 5 days | http://www.tf2outpost.com/trade/25867093 | Still unsold

1 key | 3 weeks | http://www.tf2outpost.com/trade/25720634 | Still unsold

1 key | 3 weeks | http://www.tf2outpost.com/trade/25720315 | Still unsold

1 key | 1 week | http://www.tf2outpost.com/trade/25833646 | Still unsold

1 key | 1 month | http://www.tf2outpost.com/trade/25561739 | Lowered to 16 ref, trade closed, but still in bp

1 key | 1 week | http://www.tf2outpost.com/trade/25845762 | Still unsold

1 key | 4 weeks | http://www.tf2outpost.com/trade/25667117 | Still unsold

Sellers (from Good Shiz's suggestion)

13 ref | http://www.tf2outpost.com/trade/25878375 | Open for 4 days, hasn't sold

13 ref | http://www.tf2outpost.com/trade/25877373 | Sold but took 3 days

Unsolds

14 ref | 1 day | http://www.tf2outpost.com/trade/25925599

14 ref | Young, but we have time | http://www.tf2outpost.com/trade/25936881

15 ref | ^^^^^^ | http://www.tf2outpost.com/trade/25936720

16 ref | 3 days | http://www.tf2outpost.com/trade/25904503

16 ref | ~1 day | http://www.tf2outpost.com/trade/25932421

1 key | 1 day | http://www.tf2outpost.com/trade/25930600

1 key | 1 week | http://www.tf2outpost.com/trade/25842514

1 key | 1 week | http://www.tf2outpost.com/trade/25833399

bp.tf price | 1 week | http://www.tf2outpost.com/trade/25876920

bp.tf price | 1 day | http://www.tf2outpost.com/trade/25927876

Update on proof (if changes have happened):

1 key | 2 days | http://www.tf2outpost.com/trade/25867093 | Sold, but took over a week, definitely a price which doesn't sell well

1 key | 2 weeks | http://www.tf2outpost.com/trade/25720634 | Again, sold but took over 3 weeks

1 key | 1 month | http://www.tf2outpost.com/trade/25561739 | Trade closed, started to sell at 16 ref

13 ref | http://www.tf2outpost.com/trade/25878375 | Now sold, but took over a week to sell. Considering this item is 0.8-1 keys, anything below 15 ref should be a quicksell.

I have no idea if whether this or the 13-14 ref sugg gets through :P