Sure, but printers have mass/volume and require energy. I think in all Van Neumann probe scenarios (which this is) the fact that you bring a micro—replicator that makes other micro-replicators is a given.
Right, a bacterium is proof-of-concept for a literally microscopic printer. Maybe the seed to grow into a radio dish out of asteroid materials and sunlight would necessarily be bigger than that, but I'd be surprised if it really had to be bigger than, say... a seed.
