I've had no experience with All Best Stuff, so I can't really say.
I've ordered several things from Icefalcon, and have been happy with them. The Icefalcon tool and rivets work great for doing work on the GDFB mail, I've found. As long as the ring size is pretty close, then Icefalcon's rings will work great.
The riveting tool needs to match the size/type of rivets used, for the most part. The tools I have from both Icefalcon and GDFB seem almost interchangeable though.
And of course the rings from Icefalcon should come with the rivets. So again, the only question is if the ring-size is similar to that of the mail from All Best Stuff. At 9mm, I think it is.