No, unfortunately Vignetteswitzerland.com is not selling the sticker anymore.
You can check options where you can buy the sticker here.
You can conveniently purchase the yearly e-vignette for Switzerland here.
Related articles:
Where can I buy the Swiss motorway vignette?
How much does the physical Swiss motorway vignette (Sticker) cost?
Can I remove and reuse a physical Swiss vignette (Sticker)?
Can I get a refund for a destroyed Swiss sticker?
Are counterfeit Swiss sticker vignettes an issue?