Couple.

[Paul McFedries]

> My own view is you have to explain why it's not a
> dozen of eggs before you can object to a couple eggs.

Do you also say "a pair eggs"? Probably not. Couple (and pair) seems to need
the "of" tacked on because of its verb sense "to join; to link." You have to
describe such a coupling as a "linking _of_" one thing and another. So if
the gerund takes "of", then at some point somebody must have figured the
noun must need it, too. (This is a wild-ass guess on my part.) Dozen has no
such "joining" component, so "a dozen of" is never considered.

Not that I'd ever object too strenuously to "a couple eggs" in informal
usage. Life's too short, etc. However, I once had a copy editor actually
*remove* the "of" in one of my sentences, which I wasn't too happy about.

By the way, the American Heritage Dictionary illustrates the informal "two
or few" sense with a quotation from -- you guessed it -- Garrison Keillor:
"Every couple years the urge strikes to ... haul off to a new site."

Paul
http://www.mcfedries.com/