Where's the music coming from?

Basically all you'll need though is a tape deck, blank tapes, and the appropriate RCA cable to go from the source to the tape deck.

I'm assuming the source is a computer/laptop. So this would be the cable I'd suggest. The 1/8" side connects to the output of your source, and the RCA sides go to the input of the tape deck. This would also work with a phone from the headphone jack.

There's usually meters on the tape deck and a knob for recording volume. Test the source with Rec + Play + Pause all engaged. When the level is right, unpause, wait a few seconds for the tape to advance, then start your source. Use Pause between songs to cut down on clicky noises.

https://www.amazon.com/Hosa-Cable-CMR203-adaptador-est%C3%A9reo/dp/B000068O33/ref=pb_allspark_session_sims_desktop_23_22?_encoding=UTF8&pd_rd_i=B000068O33&pd_rd_r=871c1ac4-c833-4937-8cab-253bc1fc9ebd&pd_rd_w=hv0PZ&pd_rd_wg=l38Ts&pf_rd_p=6dab4af8-14d2-4d59-b0a2-dd973ff1f166&pf_rd_r=GPCVGQR0N75BDHT4FK7K&psc=1&refRID=GPCVGQR0N75BDHT4FK7K

sumthin like this?

Although, one question I just thought of was if I use the Component cords for a 3rd Output for my PS2, what do I do with the Audio Output? Wouldn't I need a third output signal?

Yes, you'd just use audio output 3.

I would just need to get some of those audio connectors for the MVX, a couple of those Red and White cables, strip the cables and screw them into the MVX audio connectors, and then plug them into the Audio Outputs and the L and R ports on the RetroTink5x.

Sure, you can do it that way if you want. Or you can get one of these and a 3.5mm-to-RCA cable to go to the RT5X.