Performance issues with a lot of documents?
Shouldn't be. But the specific answer depends on your performance requirements and your definition of "a lot". (358 files doesn't seem like a lot to me.) Just test and see.
...but I was not sure if it was possible to manipulate excisting documents.
Corion's advice about macros is dead on. And after you have seen some of the macro code side by side with the equivalent Perl code, it gets easier to translate between the two. The Word Object Model Reference is a handy information source.

In reply to Re^3: Search and replace in multple MS Word documents by hominid
in thread Search and replace in multple MS Word documents by Wobbel

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