MC Cartridge: Elliptical; around 0.5mv; track 1.25-1.75; Affordable

Op
Just my opinion but hdm suggestion of  AT OC9XEN is likely going to be hard to beat for performance, price and matching to your present phono with fixed 100ohm input.
I think the Denon is a big nono with your present phono and you would be most disappointed and put off through no fault of the cart itself.

To Clarify:

MC Preamp: I sent the Cambridge Duo back, I will be trying a new to me MC cartridge temporarily using Bill's SUT, (and hearing a few of his MC cartridges)

to see if I get over my long standing resistance to MC,

so no mc preamp exists, anything can be matched to an eventual cartridge selection.

I do prefer staying close to 1.5g tracking as a goal
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my system is very resolving, anything right or wrong will be revealed, I just switched McIntosh SS for Tube amp/preamp last year, and all new to me TT plinth/spinner/dual arms with much help from members here earlier this year. 

solid foundation

JVC Victor Large Dual Arm Plinth (7 layers, 70mm thick)
https://www.usaudiomart.com/details/649402362-victor-jvc-clp2d-rosewood-plinth-for-tt71-tt81-tt101-direct-drive-turntablerare/images/1737857/

JVC Victor TT81 Quartz Locked Direct Drive
http://www.thevintageknob.org/jvc-TT-81.html

rear arm, Acos Lustre GST 801, changable headshell,  now Grado mono, new to me MC will go here
https://reverb.com/item/32656865-acos-lustre-gst-801-tonearm-rare

Long Side Arm, 12.5" effective 'Blackbird' (cartridge fixed to arm, no headshell). shure V15vxmr body/jico boron/sas with brush here
http://newartvinyl.ru/board/detali_proigryvatelja/tonarm_black_bird12_5_carbon/7-1-0-41

both arms into McIntosh tube tuner/preamp's phono 1 and phono 2
https://positive-feedback.com/Issue77/vintage_mcintosh_experience.htm
I have a stronger grip on this than Charlton Heston had on his rifle.

Cayin A88T Integrated Tube Amp (mki for 16 ohm taps)
https://6moons.com/audioreviews/cayin/a88t.html

Speakers: custom rosewood enclosures, electrovoice drivers from 1958 Fisher President Console: 15" woofer 15w, a 37lb beast
https://reverb.com/item/2307415-electro-voice-model-15w-alnico-magnet-15-woofer-new-in-original-box-nos
horn mid and horn tweet t350
https://www.ebay.com/itm/114194791589
original electrovoice crossovers and rheostats for brilliance and presence
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Just finished new to me TT in my office, Mitsubishi Vertical Linear LT-5V. AT440ml now, will try MC here also
https://www.vintageaudioexchange.com/product/mitsubishi-turntable-model-lt-5v

IF I get hooked by MC, it will go in main system. For compliance, my instincts are the Acos arm will be best to try MC. 

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It may seem I am being 'cheap' trying to stay below $400., but you have to admit, this MC world is full of ..., so a reasonably revealing start _____?

thanks again for help with this

To OP, 

Should you decide to get another phono stage, get one with adjustable impedance to give you more flexibility when it comes to choosing which MC cartridge. Reading your post last night, I was thinking of recommending the Hana low output, but it needs at least 400 ohms, whereas the Cambridge Duo has a fixed 100 ohms. The Hana would work with 100 ohms, but would not sound best. Happy listening. 

Just my thoughts.
Using a sut to try out MC carts is probably not the best way to start off unless you get VERY lucky.
Careful matching of sut to MC cart is a lot more involved than pot luck.
You would likely be better served with an inexpensive MC load adjustable Phonostage for your entry into the world of MC carts.

For example my Scheu SL will work loaded at 100 ohms but is MUCH more lively at 430ohms. 1000ohms is just a little too much for it to my ears.
But you need the flexibility to try and see for yourself IMHO.

A very easy recommendation would be the Hana EL....it fits all your parameters and sounds beautiful. Or buy the Hana SL with shibata Stylus......