Die Preußische Landesaufnahme (North German Map late 1800s)

On LGN's Niedersachsen Navigator Page there is now available the following item:

Neu: Niedersachsen vor 100 Jahren - Die Preu�ische Landesaufnahme

http://www.lgn.de/produkte/mapserver/homepage/index.html

This is an online map service.
This is wonderful. Has anyone used this?
One very useful feature is the "Ort" lookup table. Not so useful is that the
resultant maplet that is delivered is only available in 1:25,000 resolution, so
that when you seek to step out, the system changes to a different, unidentified
map source.

It appears that the CD of this map can be purchased. But, unless you have a Euro
account in a German bank, it does not look easy.

Is there another way (or some easy way) to purchase the CD for us in the USA? --
like with a credit card.

Robert Block