A finish nail gun would do well. They are usually 15 or 16 gauge. You can
buy a kit with compressor at Home Depot etc. that has everything you need.
Both Bostitcha nd Porter Cable have them. The Harbor Freight guns are
supposed to be pretty good and are less than $30.

I ordered a harbor freight one about 5 years ago and sent it back. While it
worked OK, and was really cheap, there was no safety on it at all. Just
touch the trigger and you shot a brad. (I know, I know....hit what you aim
at and all that, but still...)