POWER ACOUSTIK FARENHEIT MXW-12S SUBWOOFERS. Try looking them up they have yellow ones (another model) and other old school subs. If I remember correctly they handle 600 watts so they said. But do more research on the power handling it's been awhile since I've seen a set of these. Check your foam surrounds etc. Good luck.
Found some 10's on an old Singapore site here's the add if you want to see. There are other sites around just look.
Farenheit 10-inch Subwoofer Speaker . 1 unit unused
model: MXW-10S
by Power Acoustik
2-inch high temperature voice coil
Magnet 60 oz
Impedance 4 Ohm
Max input 600 Watts
RMS input 300 Watts
Frequency Response 35-3Hz
Sensitivity 92 dB (1W/1M)