Allowable Aw11 wheel offset

15x8 +25 will give you a very flush fit depending on tyre size and ride height, some run 205/50 up to 225. Guards will need to be rolled.  You can find plenty of rims in that size with dish. 
 
Personally 15x8 in +30/+35 will allow wider tyres (225's) with less guard issues.   
 
Then of course if you want to chop it up and add flares, go for a 0 offset.  

They look really good. Does anyone male replica or at least more period correct lightweight rims? Classic steel looking things and modern 'rad racer' rims are everywhere, but there's nothing that looks even close to the OEM rims of the early 80s