How do I get an infrared remote control?

rc66rx works fine in both IR and RF. Read the manual. 

They are cheaper online.

I got no manual with the remote so I went online and downloaded one.  There is no mention of how to set the remote for IR.  This remote doesn't work with my H23/600 receiver.

it's on page 12 I think. tells you how to set the remote to RF and then set it back to IR. 

Page 12 of the "User Guide" I downloaded tells how to program the AV1 and AV2 keys.  Could you post a link to the document you are looking at?

OK, the receiver is probably in RF mode. Try the directions in this article. https://blog.solidsignal.com/tutorials/how-to-reset-any-directv-remote-control/

Note all directv remotes will operate in IR.

RESOLUTION:  With the help of several here and several hours of on-line searching I was finally able to resolve the issue!  I needed IR mode and the remote comes set to RF, so:

1- Check that the receiver is set to IR.

2- "Reset" the remote.  Menu > Settings & Help > Settings > Remote Control > Reset remote.

3- Follow on screen instructions.  When they say to push Mute+Select they mean push AND HOLD.

4- Enter your magic number.  Mine was 981.

5- My TV worked after this.

6- I then programmed my AV1 button for my DVD.

Good Luck