Hi, I don't work with Atriplex, but here it grows naturally, in Mendoza, Argentina (A. lampa). May be I can find some seeds. I need a few days because I don't know if there are seeds at this moment.
Do you have interest to any Atriplex species or to someone specific species? I ask you because it is winter now, and determination of Atriplex plants to the species level may be difficult.