My apologies to the OP for taking the thread a bit off course
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. Though in a way this is all good information to better arm you in your decision. Never mind my post count, I'm practically a newb compared to the knowledge base of some of these guys here, but I've stuck around as long as I have for two reasons: 1.) to soak up as much of their knowledge and wisdom as I can so I in turn can make better decisions on my gear and setup and 2.) simply bc it's a great little community of intelligent folks with good senses of humor and I like engaging in various discussions. I would invite you to do the same and stick around awhile. Trust me you'll be better off for it.
That being said, you've got two choices: either upgrade to a 4k receiver with one of the suggestions mentioned here or get a dual HDMI output player and run your audio to your existing receiver with the 4k video fed straight to the TV. In all likelihood either option will serve you well so it's really your call as to whether you feel you likewise need an audio upgrade. If you're happy with your sound now, you can get your connectivity and save yourself some cash; put it towards better speakers or a higher quality sub and you'll likely see much more sound improvement with your existing receiver than you would by getting a new receiver with your existing speakers/sub. That's all I was trying to get at, that you don't necessarily
have to upgrade the receiver but I you've decided that you need to, these guys have offered good advice. Best of luck and hope you get what you're looking for!
PENG great post and I enjoyed the read as well thanks for digging that up!