I sent H&R an email about this yesterday and here's the reply I received:
"...you need to send us your name and address requesting the form as this mailing was only sent out to people who had bought rifles last year and sent in thier registrations forms that came with the firearm. The offer is only good for rifle barrels.."
So I have asked for this form. And I did by rifles last year - new Sportsters and sent in at leas one registration, but I haven't (yet) received this form... maybe it is only for those who bought a centerfire last year (which I also did, but they were used)..?
Cheers
Kerry