Right now, it appears as if someone posted a fused pistol skin. The option to place a buy order is therefore available.
However.
If I actually try to place a buy order on the fused pistol, my coin is returned to me instantly. It shows up on the side of the screen as coin received. So the bid is placed – and the money of the bid is returned to me instantly. It is bugged. I hope this didn’t happen to the rifle as well, as it’s beyond suprising that no one is trying to sell it.