As noted, the scam is many years old. I have not actually seen it on SA, probably because I always shut down out of town SB's that message me.
On second thought, I have seen a variant of this a few times when an SB messaged me that she needed $$ for books/tuition/etc. and she would gladly do anything when she came to my city for summer vacation... blah, blah, blah. All get the same response of essentially "no fucking way."
I did get one of these a while ago when I tried Arrangement Finders - the absolute BIGGEST scam SD/SB site on the planet, with the possible exception of Craigslist.
Said she was in the Peace Corps and was coming homing home soon to look for her soul mate. I saw this scam immediately, but decided to see how far she (probably he) would take it. We decided to message offsite and exchanged 10 or 15 emails over the next 6 weeks. Her messages increased in "I think you're my guy" crap along the way and the final buildup was when she told me a sob story about her camp being threatened by bad guys and she needed to evacuate asap. She just needed cash to fly back to the US and then we could be together. Her pleas got desperate and she hinted she was in danger of being caught, raped and killed.
I sent her a note that said: "Sounds bad. I'll sure miss you. Good luck."
[Begin Bugs Bunny voice] Ain't I a stinker? [End Bugs Bunny voice]
Of course 3 weeks later I got another email. No mention of evacuation or danger, just "I miss you and want to see you soon" sort of crap. No reply from me.