@Monsieur Jeremy you will not get a decent sound out of built-in speaker when attempting to enjoy Spotify. You might be able to link it to your Audy infotainment system, via bluetooth and your phone vial local wifi to Carpuride. I'd sooner spend a little bit more cash and bring the car up to modern standards, it'll also be more salable further down the line.
A decent Sony or a Pioneer system from hallfrauds will do the trick and will utilise existing speakers in the car.
I have been umming and arring about Alpine Halo 9 or 11 for a few years now for my work van. Not least as should I ever need to check alternative route to a job, I can't be told off by the copper that I was fiddling with my phone, whilst driving. Still need to bite the bullet.