Here's a replacement remote for $70.  But you don't need to spend that kind of money.  We know all of the IR signals for the HTR-5460.  I would probably look on eBay for a Comcast DVR remote (usually about $6, shipped).  The advantage of this remote (like other remote made by UEI, including Atlas remotes used by other cable companies) is that we can manually program it to do input  (CD, tuner, DTV/Cable, etc)  selection as well as the more basic functions like Power/volume, etc.  Use setup code 30176 (Audio 0176 on remotes which use 4 digit setup codes).