Where could I get a Peugeot 307 hatchback 2004 model owners manual

Ebay

try a dealer. he may be able to order one.
Heres is a tip. When u buy a car 2nd hand mke sure u have 2 good sets of keys & an owners manual .
Make ur offer for the car & then tell them u r deducting 100 dollars for lack of an owners manual & 100 dollars for lack of keys,,,,,,since that is the cost to u in time & money to replace them. Many times they ''amazingly'' seem to locate these items. And if they do not then they r paying for the replacements anyway.
l have done it this way for years.