Well I connected to Hoodman regarding the H-CAPD3 Hoodcap LCD and they confirmed that they don't manufacture this plastic cover. However I found 2 good alternatives: A strong protective film and a strong protective glass. Not at all expensive! I found the first one in Germany and the second one in France. Both are fitting perfectly the D3S LCD display (actually the main LCD display on D3 and D3X has the same size but not the small display below, beware of that!).
2x Screen Protector for Nikon D3S-Anti-Shock 9H Foil Dipos Glass Plastic Glass | eBay
This is the crystal clear version but it does exist too as an antireflexive film:
Screen Protector for Nikon D3S Film Anti-Shock Matte Screen Protector Display Film | eBay
Protection Ecran LCD Visière pour Appareil Photo Nikon D3 | eBay
The only possible issue with that one is that it covers the "Nikon D3S" name at the bottom of the display but I don't care. Won't impact camera performances!
I purchased both and received everything last week. I guess I'll try one of each on my 2 D3S cameras.