Dear Rapid: The Denon DLS-1 is very good performer and you can find it inside your budget. This cartridge has very very low output so you need a really high gain active ( I prefer over passive SUTs. ) phono stage.
You said that your NS10 has: Active Impedance Matching Module for moving coil , can this means that other than impedance matching has the gain for very low output MC cartridges?, if yes then that Denon is very good option.
The other alternative is to have a second ( different ) MM/MI cartridge in your Sony.
Regards and enjoy the music,
R.