How old is too old?

Buy a streamer.  It can sound better.  

There are less repairman and less parts than ever.

For 3k you can surpass your Sacd

Some good points. Thanks, everyone.

You don't forego listening to your cd's when you move to streaming, rip them to streamer internal drives or NAS. You then back up those files via something like RAID, so two drive NAS, second drive is copy of first drive. And then I have a copy of the copy via usb drive, so three drives would have to fail for me to lose my over 3.5k rips. Another possible advantage of this is cd rips may have better sound quality vs cd's with transport, mine did with the subsequent transports used after my ML No. 37 died.

Disc drives do wear out over time.  I recently went through a lot of effort to replace the pickup in my Sony XA5400ES (w/VSE mods) which is still a great sounding player.  

It’s hard to tell how much use a previously owned player has had or how much life is left in the pick-up.  So, there is a risk buying used.  Perhaps keep your search to players manufactured in the last 5 years?

Another poster recommended Esoteric which makes highly regarded disc players.  If I couldn’t get my Sony fixed I planned to get a Marantz SACD 30N which also supports streaming.

If you find a used player you like, call the manufacturer and see if they will sell you a transport. Just buy it and factor it into the total cost. If you decide to sell it for some reason, having the extra transport will make it much easier to get a fair price,