Welcome!
If I were in your shoes I'd spend your $450 on something like an Audioquest Dragonfly USB DAC / headphone amp ($100-$150) into your computer and spend the rest on some new or used headphones ($300-$350). Oppo PM3 headphones would be a slight stretch ($399 new) but with the dragonfly worth it and would give you a taste of true high end sound.
A $150 turntable is a recipe for disappointment. You don't have to spend big bucks - eg a Pro-ject Debut Carbon is a great start but at $399 almost your whole budget - and doesn't include the extra cost for a phono preamp. A $150 audiotechnica TT / cart is just going to sound thin and nasty leaving you scratching your head about vinyls appeal and soured on it.
Aren't you glad you asked our opinion?
