I'm glad you brought this up because I am clueless on Hun partridge.
Except for hen chickens from the genetic outfits such as Whiting and Metz, grading soft hackle skins lacks clarity, perhaps because the sources are so varied and consumers are not typically very picky, with the exception of die-hard fans of North Country spiders. With these skins selling for $25 to $30 per bird, that strikes me as unacceptable.
I don't know about most tiers, but I can't answer any of the following questions regarding Hun partridge:
What does it mean to be a # 1 skin? Ties down to # 22 soft hackles? Has a certain percentage of feathers that are not damaged? The head is mainly intact and therefore more useful for the smallest feathers? Is it a big bird with lots of feathers or a smaller bird and therefore with fewer feathers (the latter may be preferable).
Is there such a thing as a # 2 skin? What are the parameters for that designation? For hackle sizing, say for tying down to # 14, or a larger percentage of damaged feathers, or both?
Is the skin you get usually a male or female? Does it make a difference?
For patterns that you could use a distribution wrap or dubbing loop on, this isn't a big deal, and you can substitute all kinds of soft hackle feathers, but if by pattern or preference you are winding soft hackle, it is.
I venture to guess that Nemes or Hughes or some other soft hackle writers have sections in their books on this, but my library lacks those to refer to.
While there are a zillion tutorials and videos on "How to tie the Partridge and Orange/Yellow Soft Hackle" there is a severe deficit on the web including Youtube for what tiers neally need--material selection tutorials and videos that go in depth for each material.
I am not a web search wizard so maybe I just haven't found them.
BTW, I would hope the shop owners who sell these could answer the questions above.