Hello TMU Community!
We’ve already (and are still) doing extensive research on mattresses and all components so just need some help determining which vendors to look into and eventually purchase from. A tried & true vendor on or off the Mattress Underground trusted vendors list that provides the following in their mattress cover (FYI - to be clear the cover that comes w/ the mattress, wraps/zips around to hold the latex in, not the protector):
*GOTS certified cotton all the way through
*GOTS certified wool or equivalent batting
We preferably would like the option for a split Eastern King, and the fully customizable option to chose 100% Talalay and/or Dunlop layer combinations. Organic latex not necessary. We are more concerned about the cover components. Hope others will benefit from this as well. Thanks in advance!
AdAdamzz
Hi Adamzzz,
Welcome to the Mattress Forum! 
[quote]A tried & true vendor on or off the Mattress Underground trusted vendors list that provides the following in their mattress cover (FYI - to be clear the cover that comes w/ the mattress, wraps/zips around to hold the latex in, not the protector):
*GOTS certified cotton all the way through
*GOTS certified wool or equivalent batting[/quote]
I’m sorry I glanced over your post! 
Unfortunately, I don’t have a listing of all of the manufacturers of products who are and aren’t members here on the site, and which ones carry different certifications of the covers used in their mattresses, as that would be a far larger task than any one person or database would be able to compile in an ever-changing market.
With that being said, I did take a quick look through the site members here and found some retailers and manufacturers who offer mattresses that use some of the componentry you requested in their covers. As a manufacturer can use GOTS certified cotton as a component within the mattress cover, but there may be some other materials, and the cover itself may not be certified as GOTS certified with the completed mattress (this is not as common), I chose to cast with a rather wide net and list retailers/manufactures that at least had some of the componentry you requested in their cover, but then I would advise you to delve into further detail if the completed product meets all of your requirements specifically. I’m also listing any product using wool that’s listed as natural or EcoWool, and looking at online options only, as you didn’t list a specific location. Note that with some of these companies there may be only one or two models that meet your criteria:
Arizona Premium
CozyPure
Dormio Organic Beds
Flexus
FloBeds
Foam Sweet Foam
Latex Mattress Factory
Memory Foam Comfort (Natural Latex Line)
My Green Mattress
Nest Bedding (Q3)
SleepEZ
Sleep On Latex
Sleeping Organic
Soaring Heart Natural Bed Company
Spindle
The Mattress and Sleep Co.
I hope that helps give you a good start!
Phoenix