Help with cartridge

I am considering having it upgraded by the Needle Doctor, to the sapphire boron with nude micro ridge stylus.

Sapphire or Boron, not all together 
What's the price and why do you think it will be better than another cartridge (not a refurbished one, but a factory made) with similar advanced cantilever and stylus ? 

You have to ask about compliance of the new combo. 

Actually what Needle Doctor offering for Denon can be purchased for many vintage MM cartridges, because modern JICO SAS stylus is sapphire (or ruby) with S.A.S. profile. And a broken cartridges body like Victor Z1 cost almost nothing (fully compatible with JICO SAS stylus).

Denon is LOMC and you need a SUT of high gain MC phono stage, also proper phono cable.  

 

Sad to say it but you’ll have a hard time working with Needle Doctor (Minneapolis MN); the owner closed it last year due to poor health. I’m also pretty certain they didn’t do repairs or upgrades, just re-tip trade-ins. Perhaps you’re thinking of Soundsmith? They do re-tips and upgrades. Their boron/nude contact line diamond combo is $450.

FWIW, you might want to consider investing some extra $$$ and making a real upgrade. The Denon is a nice cartridge, but yours is rather old now and there are vastly superior carts out there brand new at the $900-$1200 price point.

Good luck and let us know what you decide to do.

Sorry, Needle Clinic (Andy), not Needle Doctor.

BTW
The Denon 103S in their literature is called "special elliptical"
but under inspection has more in common with other more complex
shapes than a typical Elliptical hence its original selling price.

Soundsmith may be great but has a very long turn around time. VAS turned around two carts for me in two weeks. He also has a very good reputation as well and is recommended in many threads.

https://vasnyinc.com/repair-service/
Billwojo