Help with filename processor

Hello,

Could someone help me with the following filename?

Alfred Hitchcock Presents 01 x 05 Into Thin Air (1955).avi

I have entered this:

(^|[^a-z]) (?<s>[0-9]+) +x (?<e>[0-9]{2,})[^a-z]

I would like it to look as follows:

Alfred Hitchcock Presents - S01E05 - Into Thin Air.avi

Thanks so much!
Mark