I'd download version 5.88, the last version 5 release, available from the Sourceforge page on Eraser. It will work; I had it running under Vista x64 for some time. But it won't work as well as it did under XP because of the changes to the Windows security model, with which version 6 is better equipped to deal.
Also, Version 5 is no longer supported; if you have problems, we may not be able to help you here.
David