There is a good chance that Strida parts do not fit!
One detail for identifying:
The slot below the bottom bracket - there is something welded next to it, right?
Ming cycle never did that - but moreover that I’d expect belt tension adjustment issues because the slot’s length seems shorter than normal!
Yes indeed - keep your hands off that offer (if it was offered as fake).
If it was offered as a genuine one - please go and slap the seller generously. 
Edit; there are more hints to be found via forum search and “SLO” 