Reply/multiple accounts: Setting From to To of original mail

[Mike]

I have multiple mail addresses and some received mails are directed
to a certain folder.

When replying to one of those mails in that folder I like to set my
>From like the To of the mail I'm replying to.

Is there a special solution for this?

Or is there a more general approach involving pipes to set a mutt
variable? E.g. when I reply in this folder, can I pipe the original
mail to a script, extract it's To and set the reply's From to the
result? Something like this?

| extract_to_header.pl | 'my_hdr From: <stdin>' ... <reply>

Thank you.