Cupped washers

Mancini Racing is where I saw that. They want $3.99 each for the washers. Thought that was a bit high, but supply and demand creates the market.
I found some that were for a Jeep CJ that looked identical, but were much cheaper. Don't know if those would work in place of the OEM ones. I tried crossing the part numbers, but that didn't work. I don't need the entire kit of nuts, sleeve nuts and washers, but locating the washers isn't easy.