If you've got a schematic and sourcecode or hex file, and can still get all the ICs, you've got all you need to recreate it, as you'd want to redraw the PCB layout in a PCB CAD package anyway so you could order the PCBs online.
Many Silicon Chip projects were republished in the British "Everyday Practical Electronics" magazine (now just "Practical Electronics") so its worth checking their archives for a couple of years forward from the original publication date as you may well find the layouts and firmware there. Article reprints are chargeable, access for firmware and some layouts is free. If you are lucky EPE PCB service may even stilo have PCBs if they republished the "Barking blaster" project. N.B. project titles may be changed to better relate to the UK market so look carefully at anything in the index with 'Dog' in its title or description.