Yes, you can download them via PDBe.
For example: for a PDB ID 1DDT, You can see the entry page here . You can see the quaternary assembly (in this case this is a homo dimer) information here. You can download the PDB coordinates from Downloads page here . Quaternary assemblies (homodimer) structure can be downloaded here:
http://www.ebi.ac.uk/pdbe-srv/view/files/1ddt_1.mmol for different PDB IDs you can either loop through identifiers using a shell script with wget or do some targeted data retrieval using modules like Mechanize