I would recommend a free antibody database available at labome.com. For Opa1 antibodies for IHC/IF you can check the following link: https://www.labome.com/review/gene/human/OPA1-antibody.html. In particular, Invitrogen OPA1 antibody (Thermo Scientific, MA5-16149) can be used for WB and IHC. Also, Novus Biologicals OPA1 antibody (Novus Biologicals, NB110-55290) are suitable for IHC. Santa Cruz Biotechnology has mouse monoclonal D-9 OPA1 antibody (santa Cruz, sc-393296) for IHC. In addition, GeneTex has rabbit polyclonal OPA1 antibody (GeneTex, GTX48589) for IHC. BD Biosciences provides OPA1 antibody (Becton Dickinson, 612,606) for WB and IHC.