They will deliver the power supply to your doorstep. If you don't have an HP printer, check with your vendor. You will probably find the power supply will not work with 50hz power. I learned that after I burned a hole in the floor after plugging my North American power supply into a converter. Cable modem service is available.
Stereos bring 'em and buy a good transformer here.
Look at your electronic device near where the power cord plugs in to the housing. Find the marks in the case or on a metallic plate which list model numbers, serial numbers, and acceptable voltages. Look to see if your unit will accept 50hz power input. If it does not accept 50hz power input, then no, it will not work even with a transformer. The transformer knocks the voltage down to 110volt, but can do nothing about the frequency.