All prices are ridiculous at the moment, they're simply not worth paying.
They need to come down to about 1/4 of what they are now, maybe even 1/8th. For the most part people aren't even buying them, just listing them at stupid values.
It's one of many reasons we've stopped caring much about arcade boards; if people have undumped boards they want to see in MAME they can loan them out / donate them, or dump the ROMs, otherwise prices aren't worth paying.
My advice right now would simply be to not buy anything. The bubble will burst, the current prices are delusional. We're seeing PCBs we had to pay to have people take off our hands 15 years ago (because the offers wouldn't even cover shipping) being listed for $500-$1000