According to the Oxford English Dictionary, it was possible in Middle English (1150~1500).
every, adj. and pron.
II. pron
†6. Everybody, every one. Obs.
c1386 Chaucer .. Every hath of God a propre gifte, som this, som that, as him likith.
(Everyone has his own gift from God — one this, another that, as befits him.)
There are a few more definitions very similar to that one, most of them † obsolete.
However, it does mention this entry that is "obsolete except in legal documents". Note that it doesn't quite correspond to your example because it must be followed by "of":
7 a. Each, or every one, of (several persons or things).
1665 Defoe .. Every of the said Chirurgeons shall have Twelvepence a Body searched by them.
(Each of the aforementioned surgeons shall receive 12 pence for each body they look at.)
Both of the above uses of every are very foreign to my own ears, and I say that despite having just waded through about a thousand pages of John Milton (1608–74). Obviously, if there are examples there are examples, but what I mean is that it may not ring true to a modern hearer, the way some things make us say, "That sounds like Shakespeare!"
One thing worth noting is that several other words of this type have, on the other hand, retained their pronominal uses, among them some, none, both, all, neither, either, and one that corresponds closely to every, namely each. Some are more poetic than others, but all are easily understood.
Here's the OED reference for one of them:
each, adj. and pron.
II. As pronoun.
3. With reference to a n. going before, or followed by of. [...]
1837 J. H. Newman .. Each has his own place marked out for him.
This is interesting since every is the remnant of an Old English compound ǽfre ǽlc corresponding to "ever each" (which the OED's version of the etymology claims were two synonyms reinforcing each other). The OED examples show the phonology of the second word gradually eroding. We might say that the pronominal sense of each disappeared from every as surely as the signs of its ever having been there.
The OED tells me that every is also a separate noun that once (19th century) meant "rye grass". This is quite a hard bit of trivia to Google given the functional status of "every" today. That might make it a good candidate to include in a riddle. :)