Basically all you need is a wall-wart that delivers 12 Volt DC with an output current capability of roundabout 150 mA. Higher current capability (e.g. 200 mA) usually won't harm, whereas you should definitely avoid higher voltage. However, on unregulated power supplies the idle voltage often is quite a bit higher than the voltage under load/nominal voltage - and if the current capability is significantly higher than what the powered device actually draws, the idle voltage might not drop far enough. So, if you were for example only able to find a model with 1000 mA, I'd strongly suggest to only use a regulated/stabilised one - and personally I'd rather go for a conventional linear-regulated model than one of the nowadays more easily available switch-mode types.
Hoewever, the single most important thing: Unfortunately Dual went cheap on the CS4xx family tables and didn't equip these with a protective diode against false polarity. So, before connecting your new wall-wart, do make sure that it's configured that way, that the inner contact on the output plug is plus/positive - 'cause otherwise it's all too easy to fry the electronics for motor speed regulation, which is integrated into the motor and hence not easy to repair...
Greetings from Munich!
Manfred / lini