Don't know what in particular your lookinh for but here's two great little ones i found not far from each other and not far from hallesaintpierre.org/galerie
http://musicfearsatan.com/ is is all metal doom stoner post hardcore kinda stuff and nice guys that run it
http://www.baladessonores.com/ this is a little boutique'y shop sells more fancy pants angular haircut stuff, i went not long after RSD and they had a lot of that stuff in some DW stuff and i got the fantastic french release of Maniac frm there, the lovely guy that runs it sorted me out a copy by getting on the phone to the label which he said is based round the corner
happy travels