I replaced bad floppy disk EPSON SMD-480L in my Atari 1040STFM with correct PC 3.5" floppy disk Mitsumi D359T7. This disk has one and only place for jumper. Withot jumper it is a PC floppy, with jumper it behaviours like Atari floppy :-)
> else where can i buy one that fits?
Mitsumi D359T7 fits 95% into Atari 1040STFM case but a rectangle push button is a little problem because Atari case has a romb hole.