Hi Pippi! Since I don't grow peonies myself I really don't have a recommendation to make. Maybe others on this forum will kick in.
I did snoop around on the internet a little and found some places that sell Red Charm, for example, here:
http://www.hiddenspringsflower...
If you do mail order be sure to check the Garden Watchdog first:
Hard to believe a year has passed and Adelman's Peony Walk 2012 is just 3 weeks away!