Hello! I noticed you were looking for some clematis seed. Not sure if you have found any or not (dont' come here often either), but will start!!
Anyway I have the following:
clematis Hagley
c. alpina "Frances Rivis"
c, "Miss Bateman"
c.viticella albo luxurians
c. petit faucon
c. Nelly Mosier
c. scarlet clematis(clematis texensis)
There were several things I was very interested in from your list:
Lobelia grape knee hi
Shaggy masterwort
helenium mardi gras and runinzwerg
ligularis britt marie crawford
thalictrum flavum ssp. glaucom
rudbeckia maxima dumbo's ears
I do have a few other clematis if you have found any of those or aren't interested. Also you could check my list(though No clematis are listed there) there are many other things. Thanks so much, Melinda PLMK.

Just wondering if you had seen my post above or not! PLMK if interested! Thanks, Melinda