I think all of the previously mentioned brands are solid performers and should do the job for you. Not knowing the ins and outs of your existing gear, my only recommendation at this point is make certain you know what you need to keep using what you aren't upgrading right now. (Your TV for example... if it has HDMI, no problem! If it didn't though, you would need a solution. (But at 11 yrs, I'm guessing it does.))
Amazon is a good place to start your research, just to see what's out there in your price range. Denon for example is just releasing the x600 series (3600, 4600), so the x500 series should be seeing discounts. There might even still be options available for new x400 series. Nothing wrong with that. Same will hold true for Marantz, and possibly Yamaha.
Shop smart, learn about what you are looking at, ask questions here!