I would use rope and eyehooks or even tacs or sheperd hook. Gosh U could even use coat hooks.
here is a tutorial for you https://www.findingsilverpennies.com/how-to-hang-oars/
Thank you so much for your suggestion. I bought the swivel eye pulleys at Lowes today & will be hanging it this weekend!
if you don’t want the hangers to show buy the double backed stick on strips for picture hanging. apply in all the flat places where the oar will touch the wall (both on the wall and the opposite piece on the
oar). Let sit according to the directions and then press your oar on!
At first I thought some hooks on the back (regular teeth picture hangers) would be perfect. But I really like Vivymcreations link to how to hang oars.
bunch of ways/ideas https://www.youtube.com/results?search_query=DIY+how+to+hang+oars