That was the first thing I looked up on google... but I didn't find anything... I guess I didn't look all that hard either. But I thought maybe some one on here would see the stamp and know what is was from. And I think from looking at the online profile that it is a Eclipse.
Run your fingers along the inside rim and there may be the name of the disc raised so you can feel it. I have found many disc names on the inside rims when there was no stamp, a misprint, or a tourney stamp.