You can do this using Win32::OLE for changes in Word.

Just read data from Excel file (with Spreadsheet::ParseExcel?). Next you need to open each *.doc file you have with Win32:OLE and make advanced search (using Word's regular expressions) for string you need (for example, monks.pl[ ]@Entry[ ]@No:[0-9]@>) and change finded string to the value you need.

Next you need to make another search (from beginning of the document) for another Excel entry.