I have an Atari 400/800 Power Supply that the fuse blew. I've pulled the fuse out, it's a 5A/250VAC fuse, but I've been unable to find a direct replacement, as I don't know the exact name for this fuse type. It appears to be a slow blow, but with a half spring. I plan on modifying the supply and adding a fuse holder instead of direct soldering in a replacement.
There is another thread that mentions this type, but I don't have enough reputation to comment and ask a follow up, so I've made this question here. Harry mentions this fuse type as the second type in his post here: Slow Blow vs Fast Acting Fuse