are there historic peonys? where does one buy them and where is the best place to buy peonys one can afford?
Yes, there are heirloom peonies that are available. Many of them hail from the early 1800's. Some from the 1700's.
I get a lot of request for information on heirloom peonies through the FAQ of the Heartland Peony Society website. So far, I have not had the time to set up an area on heirloom peonies.
Most of the oldest peonies are of cutting quality and not particularly good for gardens. They all seem to share the same detrimental quality of having week stems and large flowers.
Probably 3 of the oldest are also 3 of the most widely available. Mons. Jules Elie, Festiva Maxima, and Felix Crousse.