For mantels, these guys are GREAT!!! http://www.netease.net/amc/default.htm
Outwater.com's look a little "iffy". To fake the firebox itself I don't know what I would do. Maybe get a set of glass doors and a reproduction "fire back". See samples of both at hansonwholesale.com I don't know how their prices rate but it will give you some idea of what's available.