Well, you could read the responses to you original post. Reposting the same question isn't likely to do much good.

Personally (I've worked with VSAM as I used to program on mainframes), I'd be concerned about letting newer Perl programmers touch mainframe production work. However, if you must do this, there are many C librararies which can read VSAM files. Learn Inline::C and you can interface directly to them as if they were Perl modules (albeit, with a little tweaking).

Update: Corion reminded me that OS390::Stdio is what you are looking for. Did you look at it and find that it didn't fit your needs?