URGENT! 110 or 120 / 18" Rear Dualsport or Road Tyre Wanted

[Minxy]

I have a track day on Sunday and don't have any bike available to take for the occasion except a KTM 525. Knobbly tyres are not allowed for this track day and I need to urgently find a Dualsport / Road rear tyre which will fit the 18x 2.15 Excel rear rim. A 110 or 120 / 18" will fit the best, anything bigger won't work

If anyone has an old tyre lying around that I can borrow for just the track day I will much appreciate it!
Otherwise if anyone has or knows of a second hand tyre of that size for sale (for a reasonable price) please let me know