There has for some time been a mix up between Sedum hintonii (piaxtlaense) and Sedum mocinianum.
Sedum mocinianum has longer leaves that are more bluish with many individual long hairs (not fur) flower stems are much longer to about 16 to 18 cm in good light. Leaf petioles on the flower spike are quite large or prominent and the flowers are white with darker brown stamens.
Please note: Sedum piaxtlaense is a much faster grower than Sedum mocinianum, which can be very prone to rotting in winter..
Photo No.2 Left: Sedum mocinianum Right: Sedum hintonii (piaxtlaense)
Not for sale at the moment.
Reference photos: International Crassulaceae Network