Images in illustrator not showing

Are there any ways to show unembeded images in illustrator?

My client sent me vector files in pdf format. I can see the images in the pdf or coreldraw, but when I open the pdf using illustrator, the image is not there (because not embeded).
My client can't provide the raw images because of their contract agreement with their client.
The only way I can do now is open the pdf files using coreldraw then save it to eps then open it with illustrator. This is so in efficient considering Illustrator and Acrobat is made by the same company.