Hmmm... Since I'm not able to read/write German, I can't say if your example would be acceptable. However, I found more info!

If you go to Pelikan's student website,
http://www.pelikan-lehrerinfo.de (it's in German), and click on "DOWNLOADS", you'll find a number of handwriting-style fonts that include the modern versions of the special German letters.
These are TrueType fonts, so they should load no problem on Mac or PC.
Here's an alphabet from one of the fonts (I linked to the Pelikan site), including the eszett letter:

So in my amateur opinion, I think you've got it! [well, maybe use just a little bit less of a descender]

The proof, of course, is if your letter gets delivered with the address written with the eszett.
This thread has been great fun. I know Sutterlin is obsolete, but it's really quite unusual, and I think it's an attractive font style.. Also, the spelling reform that was mentioned as getting rid of most usage the eszett and other special usages seems to not have taken hold completely. Wikipedia has an article at
http://en.wikipedia.org/wiki/German_spelling_reform