Romans 8:3 says the following
καἰ περἰ ἁμαρτἰας (and for sin)
Many translations suggest as an offering for sin as an alternate translation. I can see how περί can mean in place of, but is as an offering for a common translation of περἰ?
No, περἰ does not normally have the meaning as an offering for. Purely on the basis of the Greek present, it is hard to translate περἰ in that way.
The standard translations of
You could make this verse fit any of the last four meanings. (My source for these definitions is Liddell and Scott's Greek-English Lexicon Abridged Edition, which is admittedly more a resource for classical Greek than biblical, but which is probably apt in any case.)
With that said, however, some scholars have made the argument that περἰ ἁμαρτἰας as a phrase has a set meaning. In, for instance, the LXX of Leviticus 5.9, we come across the following bit of Greek:
Here, περὶ τῆς ἁμαρτίας means precisely sin-offering. The phrase is a set phrase that appears in other places in the Septuagint, as a translation for the Hebrew lechatta'th (sin-offering). It seems quite likely that Paul intended this allusion when he wrote Romans 8.3. I'm not sure that it's strong enough to be the principal translation, but there's a very strong case for including it as a footnote.
A couple of references on Google Books for these ideas:
Actually, περἰ ἁμαρτἰας is frequently used in the LXX to translate the Hebrew word חטאת (chatta'at), meaning "sin offering."
You could verify this by performing a phrase search for περἰ ἁμαρτἰας in the LXX and examining the corresponding Hebrew word. For example, see LXX of Lev. 7:7.
There are also numerous occurrences in the Greek NT where the same Greek phrase is used in a context that is undoubtedly referring to "sin offerings." For example,
Essentially, περἰ ἁμαρτἰας is functioning as a substantive prepositional phrase, thus "that which is for sin," i.e. a sin offering. It's likely that Koine Greek simply didn't have an equivalent word for the Hebrew word חטאת; therefore, the Jewish authors had to employ the prepositional phrase περἰ ἁμαρτἰας as a substantive.