For Windows users,
Jeff Gilchrist had the complete set of downloads available at
http://gilchrist.ca/jeff/factoring/
However, it seems that something on the server has been moved because none of the download links currently work. I've messaged him in hopes that he can repoint the links to where the files actually are.
edit: I got ahold of Jeff and while some of the files have been lost, he found some of them in a backup. I have copied the files he was able to find to
https://download.mersenne.ca/ so if his site still isn't working, you should be able to get them from mine.