Well you have many different options depending on what programs you have. I am going to assume you have adobe reader on your Mac so what I would do if you can is pull that up:
1. Open the pdf you want to change.
2. Go the the file menu and select save as text it should copy the text from the file into a text file.
3. paste that text into a word document
4. copy and paste images from adobe pdf and insert appropriately.
5. save your word document as web page, filtered(html).
6. convert your html file into an epub file. All your images should show up correctly.