> As I haven't seen a 7448 cpucard on ebay.de it's unlikely.

7448 1.8 GHz card for 350 USD:

http://eshop.macsales.com/search/7448

7448 2.0 GHz card for 399 EUR (German supplier):

http://www.apfelklinik.de/catalog/product_info.php/cPath/148_164/products_id/402