https://www.pentaxforums.com/forums/pentax-news-rumors/114977-pentax-k-5-offi...nounced-2.html
Scroll down for a nice and big picture of the K-5 with the grip. It is easy to see the border between grip and camera, and hence how much difference the grip makes size-wise. A more general tip is to just google for it, and then click on the link for pictures that is always there when you do a google search.
As a side note - I used to use my Panasonic LX-3 with a 30-year old Osram 52 BC studio flash. The flash was bigger than the camera (which in turn is much smaller than a K-5), and I used to hold the flash with my left hand. So the flash became the grip
.
And finally a footnote to the side note: Such old flashes can have very high sync voltages, and can hence damage modern cameras if a protective adapter is not used. I only found this out after using the flash with my LX-3 for two years, so I now consider that particular combination safe, but I would not dare try connecting it to my K-5 without an adapter. It could work, but if it doesn't, it would be expensive... And the K-5 manual specifically recommends against it.