Reddit mentions of Pioneer CD Digital Music Player - Old Model

I had about that budget to build the system in my 75 Lincoln. Here’s links to what I went with other than the sub which is an older Sony 10” in a box I bought used. I run the 4s and 6x9s off deck power and use a cheap amp for the sub. A better amp would be better of course but for my budget I like how this sounds. The kicker speakers have been great for the $$$ although the 4”/6x9 combo is a little high sounding because my car is so long. Your tracker shouldn’t be as bad given it’s not 19.6 feel long like my Lincoln. Haha. If you can fit bigger speakers up front I’d suggest doing so to pull some more mids out. This setup was around $400 and sounds pretty decent considering the price. The speakers aren’t on prime for they price so a little more $ would get them faster. Also don’t forget to budget in wiring as a kit and decent RCAs will raise the cost. Also, check local garage sale sites like on Facebook. People are often offloading stereo stuff when they need money. Just beware of stolen items :(
Best of luck! Hope it all works out!

Pioneer deck $99.99:

Pioneer DEH-X6900BT Vehicle CD Digital Music Player Receivers, Black https://www.amazon.com/dp/B01KKHSYGE/ref=cm_sw_r_cp_api_i_LVU2BbJ84810C

Kicker 6x9s $61.80 and 4” $34.99:
Kicker 41DSC44 4" 2-Way Speaker Pair https://www.amazon.com/dp/B00I4D2YBI/ref=cm_sw_r_cp_api_i_TXU2Bb9XQ4N0Z

Kicker DS693 6"x9" 3-Way Speakers (Pair) https://www.amazon.com/dp/B004K5AZAQ/ref=cm_sw_r_cp_api_i_LYU2BbZ3T21ZA

Planet audio amp $59.99:

Planet Audio AC1000.2 Anarchy 1000 Watt, 2 Channel, 2/4 Ohm Stable Class A/B, Full Range, Bridgeable, MOSFET Car Amplifier with Remote Subwoofer Control https://www.amazon.com/dp/B003GSLE4E/ref=cm_sw_r_cp_api_i_v0U2Bb3PFV49C

Usually just changing the unit doesn't do much difference. I replaced my bose headunit with a pioneer sph da120 but kept the original bose speakers. I didn't notice any difference. I just replaced it because i wanted to have carplay in my car.
But i've seen the Pioneer DEH-X6900BT (never model) is cheaper. Maybe get this one https://www.amazon.com/gp/aw/d/B01KKHSYGE/ref=dp_ob_neva_mobile

Mine came with a PAC interface module that controls the JBL amp and lets you use the steering wheel controls, also retains the voice navigation. I can't seem to find the exact model that's in my car, but pac-audio.com has the different interfaces. If yours doesn't have the JBL sound system or navigation, there are cheaper simpler interfaces that will still retain the steering wheel controls. (This one is like $129.95 or something), for the radio I used a Pioneer DEH-X6900BT, $99.95 on Amazon, and the install kit and wiring harness is usually about another $25 or so https://www.amazon.com/gp/product/B01KKHSYGE/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1

This is about as boring as it gets: https://www.amazon.com/Bravo-View-IND-X800BT-Receiver-Bluetooth/dp/B016KOPSJW

There is a similar model without an optical drive. https://www.amazon.com/Bravo-View-IND-400BT-Receiver-Bluetooth/dp/B016KOPV1M

If you'd prefer a higher quality unit from a reputable brand, try https://www.amazon.com/Pioneer-DEH-X6900BT-Vehicle-Digital-Receivers/dp/B01KKHSYGE There are a minimum of buttons.

I guess I just assumed all sources we're basically the same. I have aftermarket stereo already. My main concern is SQ

https://www.amazon.com/Pioneer-DEH-X6900BT-Vehicle-Digital-Receivers/dp/B01KKHSYGE

https://www.amazon.com/dp/B01KKHSYGE/ref=cm_sw_r_cp_apa_1afxzb9KB06NZ

They're so cheap, get you some Bluetooth.