can I put 19s in the rear and 18s in the front, Im thinking about getting HRE 440r's. what width and offset would in need for the front and rear??

 

You can but I don't see a benefit of doing it. Check with HRE for the offsets and they should be able to tell you what is needed.
You are going to need somewhere around 62+ on the rear and around 50 front.

Jim