You should go fiber.
While you can extend the distance with an intermediate hub/switch to deliver the signal in good shape, the timing would be off and most likely cause a bunch of late collisions / timeouts.
Hanging that much cable out ni free space is also a bad idea, it'd be acting like a big antenna, which may also degrade the signal somewhat, and could possibly introduce bad juju (in the form of static electricity or lightning EMP) to the rest of the network.
Do fiber, IMHO, you'll be glad you did.
FWIW
Scott