After market CD Changers for Volvo

I've got a 1994 950. When I went looking around under the rear deck
some time ago, I found the DIN-ended plug and can only assume that the
prvious owner had a CD changer out there. I while later, I had to get
under the dash (resistor block for fan motor) and found a big bundle
of the wire that goes back to the rear deck.

Looks like they'd picked up a 25-foot extension cord and had it
installed. Or whoever did the installation had only that length in
stock or something like that.

The question: Since I have no idea if the radio-end has been modified
to match a particular brand of CD-changer, what are the brands and
models that I should be looking for, with a multi-CD capability (would
love a 25-changer -- it'd take me across Canada before it started to
repeat....)

I'm located in the GTA (Southern Ontario, Canada) but I can chase down
brands and retailers.

Also, which chains should I stay away from (doofuses who can't find
the butt with both hands)?