Yep, discontinued if I recall a recent GBO thread correctly.
Some alternatives might be:
1) Gunbroker
http://www.gunbroker.com/Firearms/BI.aspx?Keywords=H%26R+topper2) Used market...gunshows, pawn shops, etc.
3) Make up the configuration yourself...buy a Pardner, send the receiver in to someplace like Metaloy...
http://www.originalmetaloy.com/ ... for hard chroming, and paint the stock black. Whether it's worth doing is a personal call.
Luckily, H&R still makes those good ol' Pardners!