I maybe buying the new MGS Game today, but i am anyway mindblown by the Artwork and the Design of the Swords.
Especially what Samuelīs Murasama and the Saya Sheath belongs. I am doing the new HF Blade from Jack too, but Saya is a little more difficult to make, soooo.....more Fun!
Only Thing left to know: The Dimensions of the Katana. Without them i canīt make the Sheath.
A slight thing that may (or may not!) help you : out in the sword market there are a few forges that make tungsten/titanium coated/infused blades, they are all fairly cheap, usually running around a hundred bucks, give or take. They also are very, very red. You can use these blades as the base for Sam's sword, and it'd be functional to boot (and can be dulled by the forge if you wanted). Example: [link].
But i think i will go with Wood anyway, 1st the Murasama is longer and 2nd i donīt want it sharp^^