SIMATIC HMI IPC 477C / PC 477-HMI/RTX

Dears ,

Good day for professionals .

I have problem in our PC 477-HMI/RTX PN:6AV7843-0BD10-0MB0 ,power board problem and tried to repair but in vain.

Now I'm going to buy new one , but for our bad luck I can't find same model , only available in market successor type SIMATIC HMI IPC 477C PN: 6AV7884-2AB10-3BL0.

I know difference in supply voltage from 220Vac to 24Vdc .

Also I tried to change device type fromPC 477-HMI/RTX toHMI IPC 477C using WinCC Flexible 2008 SP3 UPDATE-5 but I can't find HMI IPC 477C .

Now my question is , Why I can't find requested device type although software last updated , also if I buy new type SIMATIC HMI IPC 477C can it do same job or may I will face new problems.

please for your urgent advise .

regards

Karam