Looking for Ferula seed sources

I'm looking for seed sources of various Ferula species.
My aim is to either recreate the ancient spice/vegetable silphion or something similar.

I assume these two species will probably be much easier to get as they are used commercially to produce "asafoetida"
F. assa-foetida
F. foetida

Other species I am looking for I think will be rather difficult to find:
F. persica
F. szowitziana
F. alliacea
F. drudeana
F. tingitana
F. communis subsp. brevifolia
F. anatolica

I'm also looking for information on what Ferula species grow in northern Libya (which is where the ancient spice was originally grown)