Export pads as a pdf file in Altium
In a PcbDoc go to File -> Fabrication Outputs -> Final

There you get a print view of all layers. You can select the ones you want and print to pdf. Make sure you have the scaling you want. 

In the configuration you can select for each page the layers you want to see. By selecting "Create Mask Set" you get the Paste and Overlay layers only. Remove the Mechanical.