Best phone preamp for around $500?

I’m setting up a Pro-Ject Debut Carbon DC Esprit with my KEF LS 50 Wireless speakers and need a preamp. Currently it has the Ortofon Red cartridge in it but I’ll probably upgrade that to Blue or Bronze eventually. I’ll most likely upgrade the turntable as well to something like a Pioneer PLX-1000.

What’s a good new/used $500ish preamp to grow with? I’m mainly looking at the Pro-Ject Tube Box S2 and DS.

Thanks for any input.