Greetings,

From countless hours of digging around in the game files for modding purposes, I've collected a minor list of items that I have not noticed are obtainable from within the actual game, despite my many playthroughs. Some are probably just left-over items that never made the final cut, but it's still interesting to see if someone else might have stumbled across them, somehow.

GOLEM TROPHY - Golems in the game drop the Elemental Trophy, rather than this one.
NECROPHAGE TROPHY - This one was probably replaced by the Rotfiend Trophy, as they have the same in-game model (although a different inventory icon and different stats).
DRAUG'S CONFESSION (in-game name)/Draug Testimony (resource name) - A silver sword with a unique (beautiful) model, and some crazy-high stats. Never seen it.
GVALCHCA - A silver sword with a unique model. Never seen it. I'm not sure what the name is supposed to be, but to me it sounds eerily similar to G'valchir (the actual name of the Mahakaman Rune Sihil, which can be imported from TW1).
NILFGAARDIAN LAWGIVER (in-game name)/Nilfgaardian Essenced Sword (resource name) - A steel sword with a re-used model. Never seen it.
SWORD FROM THE ARENA (in-game name)/Arena Blade (resource name) - A steel sword with a re-used model. Never seen it.
SUPERB DOL BLATHANNA SWORD (in-game name)/Dol Blathanna High Quality Steel Blade (resource name) - The tier 3 version of the Dol Blathanna steel sword, with a unique model. Never seen it.
LEATHER JACKET (in-game name)/Light Chainmail Shirt (resource name) - A piece of armor seemingly balanced for near-end Act 1, which shares the model of the Hardened Leather Jacket, and carries the same name as the Leather Jacket (starting armor).
HEAVY ELVEN ARMOR - A heavy version of the Elven Armor with a unique model. It exists in the resource files both as a diagram and an item, but I've never found either anywhere.

Trophy's seem to be dropped somewhat randomly. (Anyone else wonder how a trophy hanging from your belt buckle gives more armor and other stats boost?) So, it may just be a matter of replaying the game enough for them to show up. Golem Trophy does sound familiar to me though, same with the Necrophage Trophy. Thing is; I sell the damn things immediately; the Kayran trophy gives the best stats boost, so I can't remember.

I think I've seen the Nilfgaardian Lawgiver somewhere; it was either at the end of Chapter 2, possibly in the Nilfgaardian camp, or at the beginning of Chapter 3 somewhere, possibly in a cave. But I'm not certain.

None of the others ring a bell for me.

I found the Elemental trophy at the Golem guarding one of the chests in act 3.
I'm not completely sure without checking an older saved game, but I think I found something that sounded a lot like GVALCHCA somewhere in act 2, Iorveth's path, when going to the other side of the mist.

Gval'cha means "falconess" - it's actually a name in modern human languages, the name Falka.

Mass-murdering rebel, burned on a stake and Ciri's ancestor. Ciri actually used the name Falka as an alias, when she was pillaging South with the Rats.

They vary from very high to very low drop rates, yes, but I've never ever had anything but the Rotfiend Trophy drop, nor have I ever had the Golem Trophy drop from one of the golems you meet in game - they've always dropped the Elemental Trophy (or nothing at all). Hmm... Never seen it, myself. You can get the Nilfgaardian Harpy in Chapter 3, which is the model the Lawgiver re-uses. Yep, there are several elementals/golems you encounter throughout the game, and each one has a chance to drop the Elemental Trophy. You might be thinking of the steel sword Gwalhir, which is given as a reward for a quest near the end of Chapter 2 (Iorveth). Ooh! Thanks for that tidbit of trivia. I'm always fascinated by lore-related stories behind the names of items. Now I want to find this sword even more! :D

Actually, Temerian and Redanian kids still burn Falka's doll at the Saovine, akin to Guy Fawkes. Guy, however, did not kill lots of his family, burn many cities and skin innocents.

"Krew na twoich rękach, Falka,
krew na twej sukience
Płoń, płoń, Falka, za twe zbrodnie
Spłoń i skonaj w męce!"

The song kids sing. It can be translated poorly as:

"Blood on your hands, Falka,
Blood on your dress
Burn, burn, Falka, for your crimes,
Burn and die in torment!"

Yup, Temerian kids are cruel.