I believe I did something like what you are talking about, and it took a lot of programming and conversions. It didn't seem like there were any properties from the printer that match the properties in Crystal.
What I did was create a combo box with the paper sources that Crystal accepts, and when a user selects a printer, it displays the sources both Crystal and the user selects.
It sounds like in your case, a user is selecting a paper source from the printer, and you want to send those details to Crystal. My general strategy was to take the size from that selection, and pass them to the Crystal part as a custom paper size. So, if a user selects an A1 paper size, take the width and height, convert it to a common size like PX if you need, and then set the Crystal component to use them.
The point is, there is no one-to-one conversion. It doesn't seem to be a standard that you can pass back an forth.
My application that does it is at this site:
http://reportviewer.biz/
Hope that helps.