Hdmi cable box to rca receiver

My old xfinity dvr box connected to my TV plus the box also had 2 female ports for my RCA jacks  that connect to my external receiver audio.  I just got a new xfinity box.  It has HDMI output to the TV and an HDMI port for an additional connection out (in place of the female rca ports, which one could use for an external receiver.  Trouble is my receiver only has RCA jacks.  Please recommend an economical HDMI to RCA converter for audio.  I would plug the DVR HDMI cable to the converter and then I would plug my 2 male rca jacks into the converter then out to the receiver.  Hope this is clear and thanks.