I recommend checking a free antibody database available at labome.com. For antibodies to Nampt (visfatin) you may use the following link: https://www.labome.com/review/gene/human/visfatin-antibody.html. Abcam has anti-Nampt antibody (Abcam, ab45890) suitable for western blot (Oppenheimer et al., J Bone Miner Res. 2014). Also, Santa Cruz Biotechnology provides anti-Nampt ab (Santa Cruz, sc-130058) for western blot or IHC (Chang et al, Int J Clin Exp Med. 2014). In addition, Bethyl offers rabbit polyclonal antibody (Bethyl Laboratories Inc., A300-372A) (Bertoldo et al, Mol Cell Endocrinol. 2016). Sigma-Aldrich has rabbit polyclonal ab AV42255 for both WB and IHC (Zhao et al, Mol Med Rep. 2015).