Each of the shapes has a major dimension conveniently vertical by the looks of it. The pad might be horizontal, though.
Let's say the pad cut-out is 3 inches diameter. Now take a shot of the dog that goes there then frame the dog with a circle or ellipse selection in your review image. Then measure the major dimension of the selection in pixels in the review image **, say 900px (convenient for my advice). Now you know the target inches and the number of pixels to squeeze in there.
Ergo, set the print ppi to px/inches = for example 900/3 = a convenient 300 ppi,
irrespective of how you crop the review image and irrespective of the paper dimensions. If you have a decent editor, you can set the ppi to anything you need and ignore what the driver tells you to use for your image size and your paper size.
** if you can't do that, time to download the GIMP ...