Can the volts and\or amps in a repalcement DC power cord vary without problems?
This is discussed in many previous posts, and I really should find a link, rather than answering it once again...

The voltage of the new supply must match the voltage required by your device.

The current rating of the new supply must equal or exceed the demand of the load.  The current rating on a power supply is the maximum current it is designed to deliver, but it won't force that current into the load - the load will only take the current it requires.