This Lophophora cv. cuatrocienegas co  started from seeds ordered from Germany; after seeds are germinated for a week, I moved seedling and grafted on pereskiopsis stock.  It is 1.6 cm. in across and 6.4 cm in height (from base of stock to the top of scion.  It is about 3 month old. The plant will be shipped in bare root.
I learned that pereskiopsis stock is eary to grow plant.  I used to remove the stock with scion out of the pot (bare root) and leave it outside; the plant can survive more than 4 weeks or longer with little wilt or shivel.  After put it back to moisture soil and keep watering and place in shade place, it can return to strong condition very fast.   This grafting is suitable for demonstrating grafting technique to your kid or students, or being souvenir to your special persons.