Advice on buying turntable under $500

you hardly give anyone knowledgeable any useful information to provide a recommendation

OK. I’m somewhat puzzled by what additional info you’re looking for, but I’ll try. I already have a receiver with an integrated phono amp, though I’m not averse to picking up a dedicated phono amp in the future to give it a boost. The turntable would just be for listening at home. Mostly rock, some jazz. Over 1500 LPs. What other info do you need? Receiver is a Yamaha R-300 refurbished in the last 18 months. Speakers are Cerwin-Vega LS-8 bookshelf. VERY modest setup, thus the $500 price point. Does that help?

For 350 bucks this Pioneer PLX-500 direct drive should be a nice fit!
https://www.zzounds.com/item--PIOPLX500

Save more money and get something better.

Depends on what you want, and what you mean by "showing its age". A table from the 70's can still be fine but the bearing will go dry if not cleaned and lubed in all that time. Same thing with the arm. Cartridge could even be shot. In a world where every little thing matters you're just not giving us much to go on. 

Also if the goal is sound quality the receiver is probably a whole lot weaker than the table. 

You might want to consider a little refurbishment of what you have, along with a new cartridge, as a lot more bang for the buck than a whole new table. 

That said, if you like the Fluance get the Fluance. It for sure will be a big improvement- if for no other reason than it comes with a new MM cartridge, which is probably what you really need.

Hi,
unless your tt has no issues, a new mm cartridge would be wiser and save you some money. Something like a Nagaoka MP-150/200 would be quite good.