Hello,
I see what you mean there is no way to make this happen automatically, you will need to enter each of the NAT statements one by one,
This has been discussed previously on this place.
I have seen this "workaround mentioned before"
access-list 101 permit tcp host 192.168.2.1 any range 2000 2100 any
route-map NAT permit 10
match ip add 101
ip nat inside source static x.x.x.x y.y.y.y route-map NAT
But I have never play with it so I cannot tell you that it will work.
It would be easier ofcourse to get a dedicated IP address but that involves money,
Regards,
Jcarvaja
Julio Carvajal
Senior Network Security and Core Specialist
CCIE #42930, 2xCCNP, JNCIP-SEC