SetTimer is better than sleep for something like this.
#Persistent
; Put this wherever you want, like inside a hotkey
; Either set the clipboard to some text, or just remove this
; to use what's already there
Clipboard = This is some text to paste
SendInput ^v{Enter}
last_text := Clipboard
SetTimer, RePaste, 60000
return
RePaste:
; The clipboard can change in a minute, right?
; so we use the text we had before
tmp := clipboard
Clipboard := last_text
SendInput ^v{Enter}
; And restore what the user had
Clipboard := tmp
return
; Put this somewhere, like in a hotkey, to turn off the timer
SetTimer, RePaste, off