Try Google Doc Viewer. Just embed an iframe in your page pointing to Google Doc Viewer and specifying the PDF file you want to display. This is the code you should add:
<iframe src="http://docs.google.com/gview?url=http://infolab.stanford.edu/pub/papers/google.pdf&embedded=true" style="width:600px; height:500px;" frameborder="0"></iframe>
Then you just need to set up your own document file (use absolute URL) to the "url" query string param and that's it!