Hi,
Yes but not quite one click if you count the preparation!
Open the template layout from Print Properties - Custom
Set the number of "Copies to Add" to 8, see screen shot below.
Select the thumbnail
Click the red + button adjacent to the Copies to Add box; NB. the + becomes red once thumbs are selected
That will load your template with the 8 copies of the one image. Done
Don't forget to set Copies to Add back to 1 when finished 
Terry

Hi,
I cannot find a way at present. I tried loading a template and set the number of copies to 8 and then saved that as a job. However when the job was recalled, the number of copies was not changed.
Maybe Mike can suggest something or make that a new feature in some way.
Terry

Hi,
A little bird has flown across the Atlantic that tells me that saving the number of copies may well be on it;'s way soon 
Regarding easier access to the Custom size menu, Mike is aware of your request.
Terry