Interesting project,what engine does it have? I think the last time I worked on one of those was 20 years ago??.The rear suspension may be a problem? Its unique to 305 vans & estates.The taper roller bearings in the radius arms destroy themselves,you will need special tools to get it all apart.The rest of it is what you may call normal type of design,quite easily taken apart. The man for spares is Dean Hunter
http://www.peugeotparts.co.uk" onclick="window.open(this.href);return false; I bet he will have everything you want.
If you want to meet up with some 305 owners and may be get some ideas, go to the annual Peugeot Owners Club Rally at Rockingham Castle nr Corby on Sunday 8th September.