The Dish Network User's Resource
Dish offers a UHF upgrade kit which includes the remote and a cone to receive the UHF and send IR to the receiver. Works with all IR receivers except the DISHPlayer.
The RCA DSS remote control extender works fine with the DISHPlayer (and everything else). They are available at Wal-Mart for $39.95. Spare senders are also available for $29.95.
Watch your local WalMart for a sidewalk sale. Apparently, the “spare sender cones” aren't selling, I picked up two senders at my local WalMart for $5.00 each. (This clearance is long past.)