Flexus Comfort said as of 4/2020 they are sourcing from Radium (see here)
From a few posts on this forum, it appears that Sleep EZ, Flobeds, and Arizona Premium Mattress have sourced Talalay from both Radium and Talalay Global in the past, so they might be good candidates.
Savvy Rest says that they use Radium’s Vita Talalay in their mattresses (see here)
It looks like a lot of mattress retailers aren’t exclusive to Vita Talalay or Talalay Global and switch back and forth based on various factors.