Modern pistachio trees are simply not grown and then wait for the results. The nut you buy to eat will not germinate to produce a tree from which you can obtain more nuts.
Trees are grafted onto a rootstock (either after plantation or in nursery stage) and the tree takes off from there...
The rootstock seeds are notoriously hard to find and generally take several months to germinate even if done properly. I'm lucky as I now have a rootstock tree (from a graft that didn't take) that regularly produces several thousand seeds.
It's at least 2 years from ungerminated seed to a position to plant in the ground.
I'm a commercial grower and I need to give nurseries a 2 year notice when I want some more trees, so now I germinate my own, but have 4 HA of 20 year old trees to get cuttings from too.
Take my advice....if you find a tree to buy, buy them.
Remember pistachio trees are dioecious, which means you need a male and a female tree. About 1