I have one available for sale if you want one. I've been putting off selling it for quite some time but I'd let it go for a reasonable offer if you are serious.
Great condition, 12500 actuations, 8 batteries, 2 new batteries in box & 3 chargers. I generally use a digital camera battery external battery pack and this is available with the back too if you want it. I also have a spare IR filter and an original 645AFD focus screen too.
I have been using two backs for a long time. This is the best one of the pair and the only one that I've kept for quite a while. Everything works 100% including power and firewire connections. No issues whatsoever.
Send me a private mail message if you are interested. Where are you based?