I though the USSBS files were in PDF on the Hyperwar website, but only a part of them are here, almost all on the Pacific theater:
http://www.ibiblio.org/hyperwar/NHC/...bing%20Survey/
There are three files on Japanese cities, roughly the same subject as for Lubeck, so you maybe use it for comparison.
Such government files usually end on Amazon (with just a new cover page), but in your case no luck. I could still find some USBS reports, for about 10$ each.