<p>I need to replace the lid of my water kettle and am searching for a filament, that is suitable for this purpose. The requirements are:</p>

<ol>
<li>Stable at 100°C (212°F)</li>
<li>Resistant to steam/moisture</li>
<li>Food-safe</li>
</ol>

<p>Has anyone experimented with this or similar purposes?</p>

There are few materials that go up to that temperature and beyond.
A very nice generic overview is given by
Simplify3d
:
This figure shows an overview of many of the used materials in 3D printing
When looking closely, and without pointing to specific brands (to avoid a commercial posting), your best chances for appropriate filaments for your application is to look at Nylon, Polycarbonate (do not consider Polypropylene; that is very difficult to print) or (not mentioned in the overview as they are more recent filaments) Co-Polyester polymers.