Having just sold my 500 c/m, I now turn to some a most useful accessory: the PME 90 metered prism viewfinder for $550 shipped CONUS.
This meter is absolutely awesome and provides metering capability to a V series Hassy comparable to my Sekonic light meter and any DSLR I've ever owned. Perfect exposures time and again with this PME 90.
After reviewing KEH and the big auction site, I am putting it up for sale here for $550 shipped CONUS. The condition is mint, and it comes with the box, manual, and cap. I am also including the battery.
The following pictures show the outstanding condition of this PME 90:
Although the 500 c/m is sold, you can see what it looks like on a V body:
