I think I noticed that some of the radicals Heisig presents are actually complete kanji, but are not listed as that (I suppose just because they're quite rare and not in the jouyou list). For example, I'm pretty sure the radical *Scorpion is a kanji with a different meaning, but does it apply also for *Turkey?

Is there on the net a list of Heisig radicals with their real meaning (and maybe parent kanji were they are not kanji by themselves)?
I know I should be able to figure them out myself, I'm just asking if someone did this job already.

Frames 2033-2034 in RTK1, 2090-2105 in RTK3.

You can paste a kanji containing a primitive that you suspect to be a kanji into http://tangorin.com/kanji/ - if the primitive is a kanji (or a radical), it'll show up in "Elements".

The only word the kanji 隹 appears in is the name of the radical. 也 is mostly used in names. I've never seen なり written as 也 but the Green Goddess has a couple specific examples in kanji, so I trust that it sees some use.

It depends a little bit on what you mean by "kanji by themselves" -- almost all the radicals are, in theory, "kanji by themselves" in the sense that they have been indexed and given a pronunciation at some point in time. But a lot of them are basically never used (and often never were).

As for 也, it represents the classical copula なり (not the verb なる). It's hardly ever used in modern Japanese in this way; even when it shows up in a set phrase or quotation it's usually changed to hiragana. But in pre-Meiji Japanese it's very common.