Kinko's or Office Depot usually have a machine in-house to enlarge up to 36", for not a few bucks.
I've done it at OD to enlarge/copy full size patterns.
Otherwise, if you can get your hands on an overhead projector, you could project it onto a wall (covered with freezer paper or newsprint just to make the copy), and make a larger version that way.
And another option.... would be to take the design and grid it - maybe even print it out on a piece of grid paper. Then copy it square by square to a larger grid for the size you want it to be ...that eagle has mostly straight lines so it shouldn't be that difficult to transfer. There's a name for this method but it escapes me at the moment. :roll: