Best bet in Ebay. Price for a working yoke including shipping is usually around $100. Which seems like a lot but if you think you will have the arcade machine for years and years.....then what is $100 over many years. Not much.
Anyway, I do not have an extra yoke. Sorry.
PS: I hacked a StarWars yoke, Spy Hunter steering wheel, Sega Hang motorcycle assembly, two VirtualOn joysticks, 2 sets of VirtuaRacing gas/brake pedals, 4 types of shifters and around 20+ buttons.