Mamiya 645 1000s flip-up magnifier for prism finder

Does such a beast exist? I see there is FD-401 which is advertised for Super, but does it fit 1000s? Even if with a little help from a Dremel Did anyone use it and find it helpful with getting precise focus?

Thanks,

Eugene.

I think something this will work, although it's not a flip up. It should just slide up to remove.

Duh, include link!

http://www.ebay.com/itm/like/271577249993?lpid=82