Is it a good idea to buy CD players over 10 years old even it is a reliable brand?

Opinions vary. I would not; there's too much chance of mechanical failure.

@bimmerman2 mentioned the Philips TDA1541/1543 DAC. I discovered this rather spartan CD player currently available using a TDA1543. However, don’t know whose transport is used. Top loading takes the tray loading mechanics out of the equation. The price certainly isn’t bad.
http://sparkler-audio.com/portfolio/S503_en.html

Also stumbled across this list of players using the TDA1541 along with the transport type.
https://www.dutchaudioclassics.nl/Overview-Philips-TDA1541-based-cdplayers/

Just blew a grand on an old LINN IKEMI cd player.  Sounds better than streaming with the 5k dollar DAC I have. You need a have a state of the art DAC to surpass old reference cd players. So buying an old cd player is not a waste right now. Plus it's always fun to scavenge record stores for CD'S and if your cd player has a drawer mech like my LINN then it's really cool to play CD's. 

From costly experience I would advise only buying a second-hand CD player if the full transport mechanism is still available. Furthermore, if you like the sound of the player you buy, I would budget for purchasing a spare transport as soon as possible, and keep it safe. 
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My old Naim CDX died and a new transport is no longer available so I purchased another CDX, thinking this was a one off. That too had the same issue after a time. It appears it is common for a Naim CDX to give up at the 20 year mark. It was an expensive mistake.