Newest router I have is over 10 years old. I have I think 5, just use one, because it works, and I usually only use one type of bit. I'll keep using it until it dies, toss it, then use one of the others, because they all work. That's my answer to parts availability/non-availability for old routers; get old, working, routers, cheap, and use them as long as you can. For what I do, and how I do it, this works very well for me.
"It ain't what you're told, it's what you know." - Granny Weatherwax
Some days, the supply of available curse words is insufficient to meet my demands.
Call me a craftsman, artisan, or artistic, and I will accept that. Call me an artist and you will likely get a quite rude comment in return. I am not a @#$%ing artist.