I looked into buying just the sheets or a topper after returning the one I trialed. I really enjoyed the feel of it, but not to the tune of $2000(!) for a twin(!!!).
In a different life I'd consider setting up a buckling column gel manufacturing station and just sell people custom sized buckling column gel sheets.
https://www.alibaba.com/product-detail/Foldable-Supportive-T...
Any danger with chemicals?
1. The HxW dimensions didn't necessarily match anything I wanted well. I needed four toppers to make the original mattress and offhand it looks like I could probably make it with four gel sheets from alibaba but the cuts would be more complicated to lay out and attach.
2. The thickness was listed at 4cm vs the 2" thickness of the buckling gel from intellibed. 2" is about 5cm.
3. Despite the intellibed toppers coming with a useless amount of foam, it wasn't actually any cheaper per square inch to order the gel from alibaba at the time, not that either was especially cheap. Numbers may have changed by now.