According to this article from 1998, Stephanie's fingerprints were compared to prints found in the Reinert car but didn't match, so hers are out there:
The same article states an informant had interacted with Stephanie as late as 1979
It's also mentioned she was a prostitute.
http://articles.philly.com/1998-12-28/news/25723949_1_ironclad-alibi-informant-investigators
Profiles for both Stephanie and Eddie have been added to NamUs.
Stephanie: https://www.findthemissing.org/en/cases/34827/
Eddie: https://www.findthemissing.org/en/cases/34828/
I just stumbled upon them today, too.
Given their lifestyle, they both should have fingerprints on file somewhere that they can scare up.
Per the article I posted a little while ago, Stephanie's are on file someplace.
One more time - if anyone feels strong enough to put boots on the ground for Stephanie, Eddie, and the Reinert children,let me know. I want to walk the earth they trod, search the very soil. There is an answer, convoluted though it may be and I want to find it. If anyone is interested, just say so, we will walk and search it together. Book by book, inch by inch and place by place. Let me know.
I was able to find more contemporary images of Stephanie and Eddie. Both are mugshots.