Data I/O 2900 system disk?

[Mark KAHRS]

I obtained a Data I/O 2900 programmer at Dayton in rather grotty but
serviceable shape.  But it is missing it's little old floppy (the
disk, not the drive).  The Data I/O website is silent on this.
Anyone know where to find one?

Also, to add to Ethan's Dayton report: I saw several Ultra 1s
[one going for $5 at the end of Saturday] but no DEC, No SGI
and certainly no Xerox Altos.