It's from Angel After the fall, issue 9, page 11.
Look at the difference between the original sketch and the colored&inked page. Runge didn't do his own inking like with the Wesley-story in First Night, so it ended up quite differently(I'm not a hundred per cent sure he inked all the pages, but that's what I got from his e-mail). Also, the page was stretched out horizontally. It's not that noticeable on Spike, but some of the girls' faces look weird.
If the pics won't expand, click on the links.
More pics to compare the difference;
A photograph of the original art page(the picture above is a scan).
A pic of the writing on the backside
Here's another Nick Runge page(that I don't own). Issue 9, page 12.