Please help me decide...

Hello to all...

Money is always tight so I'm a real budget audiophile (unless I believe the piece is SO incredible for what I'm getting: example JOB INT integrated amp) so since I can spend up to $445 for My Christmas present, I'd like to improve the sound of my game room/ kitchen-dining space system.

I presently have a 2002 Pioneer DV-37 CD/DVD player with Silnote Audio Morpheus interconnects, playing into a Monoprice Hybrid Stereo tube amp (50w  with 2- 6N2 (=12AX7) and 2- 6P1 (=6AQ5); speaker cables are twisted 14g solid-core copper wire, biwired with bare wire ends. Speakers until recently were a pair of JBL L25 PRIMAs but are being swapped-out for KEF Q1s, presently w/o sub.

OPTIONS: Should I:

Buy a new SS Yamaha, Denon or NAD Integrated, or some other vintage SS integrated?

Or should I buy new tubes for the Monoprice ? And add a BIC Subwoofer?

Or should I buy a Vintage Marantz SA-8001 SACD Player (which is what I have in my main system, with the JOB INT).

Or what? Your thoughts please...