PLANET ALGOL

Revised
Beholder - Eye of Terror; Sphere of Many Eyes *
Bullywug - Batrachian; Thugtoad
Carrion Crawler - Carcass Scavenger; Corpse Creeper *
Displacer Beast - Phase Tiger; Displacer; Coeurl *
Githyanki - Astral Raider
Grell - Beaktopus
Kuo-Toa - Ponaturi *; Koa-Tau ?*$
Mind Flayer - Mind Eater; Cthonoid *; Thulid; Brain Lasher; Thelidu
Slaad - Senufio; Ogdoad **
Umber Hulk - Wenge Goliath *
Yuan-Ti - Naga; Ophiduan **$

? - ?
* - To my knowledge these monsters are not Open Content
** - Third Edition statistics
$ - To my knowledge no free version is available

The monsters that I'm unaware of having any OSR-ish direct analogues are:
Githzerai - I admit, they don't exactly set the imagination on fire
Hook Horror

While trying to get to the bottom of whether the Slaad are open content under the 3.0 SRD I came across this tidbit:

"The following items are designated Product Identity, as defined in Section 1(e) of the Open Game License Version 1.0a, and are subject to the conditions set forth in Section 7 of the OGL, and are not Open Content: Dungeons & Dragons, ... tanar’ri, baatezu, ..."

Dear WOTC, I assure you that you really don't have to worry; this is like someone putting a high-end car alarm in a beat-to-shit, rusted-out '82 Honda civic.

Some lame duck attempt to weasel out of the 80s satanic panic spotlight is considered an "intellectual property asset?" Hohoho. Has anyone, ever, in the history of D&D actually used those terms while actually playing the game?

When WOTC released all that OGC/OGL jazz they took care to firewall a bunch of classic D&D monsters behind a product identity clause.

With indie publishers beings the wacky scamps that they are, a bunch of them has released versions of many of prohibited pre-2E monsters with the serial numbers filed off.

I'm working on some comprehensive simulacrum D&D encounter tables and have been using these versions to fill in some gaps; so far this is what I've come up with:
Beholder - Eye of Terror from Labyrinth Lord Advanced Edition Companion
Bullywug - Batrachian from OSRIC; Thugtoad from the Swords & Wizardry Monster Book
Carrion Crawler - Carcass Scavenger from Adventurer Conquerer King Labyrinth Lord
Displacer Beast - Phase Tiger from Adventurer Conquerer King Labyrinth Lord
Githyanki - Astral Raider from Ancient Vaults and Eldritch Secrets (a pretty "loose" version compared to the ultra-detailed Fiend Folio entry but it's there)
Grell - The Beaktopus makes for a workable substitute...
Mind Flayer - Mind Eater from the Swords & Wizardry Monster Book; Lasher from Mutant Future; The Thelidu from the Swords & Wizardry Monster Book are pretty close to the Mind Flayer, but their hit dice are significantly lower
Slaad - Bat from Ancient Vaults & Eldritch Secrets has kindly assembled the Senufio; Claudio Pozas made the Ogdoad for 3E, but they're a bit far from the original for my liking.

The monsters that I'm unaware of having any OSR-ish analogues are:
Githzerai - I admit, they don't exactly set the imagination on fire
Kuo-Toa - A whole lot of fishmen & Deep Ones out there though
Umber Hulk
Yuan-Ti - A whole lot of snakemen out there as well, but I haven't come across anything that closely replicates the AD&D version

Are any of you folks aware of additional versions of the "product identity" monsters or non-open pre-2E monsters that I have missed?