Macro - Extracting a number from a string

Dear group, 

I got the String from PslSourceString.Description[1]. This string contains the resource ID from MFC application. How could I extract this number from this text? 

The containing numbers could have 1 to more than 5 digits. Also the text in front of the number is not the same[2]

 

[1] E. g. : Zeichenkette 15002 in String Table

 

[2] Examples: 

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