Kasnakambaram seeds.

Even amazon .Sells Kanakambaram seeds.3-95 per packet.

It is not a perenneial, best a Biennel. When the seeds fall they germinate later like Malabar spinach in my yard..

That is not the only source Just search in Google Crossandra seeds.

Several venders sell them here in USA.

I also like tuberose and nightqueen