Preamp 47K load. Cartridge needs 330 ohm

A 1:10 SUT is perfect for your needs. And no cartridge has an absolute requirement for a single particular load resistance. A 1:10 SUT will result in a 470 ohm load and that is just fine for your cartridge. See above for other viable solutions.

your cartridge is 0.35 signal strength; it's coil impedance is 2.5 ohms

the answer:

Exactly as said above: Step Up Transformer with a (+/-) 1:10, ratio (which is it's xFactor),

Like lewm said: result of 1:10 x factor will change your cartridges 2.5 coil impedance to 470 which will be 'shown' to your PV7 MM Phono input'.

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the math:

your .35 cartridge strength will be  Stepped Up (multiplied .35 x 10 and be increased to 3.5V, a perfect strength for your PV7 MM Phono Input.

Impedance load is a 'guideline', kind of a minimum that the cartridge wants to be 'shown to PV7'.

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Choosing a SUT, the indicators on the front often do NOT tell you the xFactor, you need to find out/ask which SUT has a transformer inside which can do a (+/-) 1:10 xFactor. 

i.e. my SUT, Fidelity Research FRT-4 (I had to find the specs) has optional indications on the face, the face option of 100 ohm results in an xFactor of 10.55. which results in 423 ohms 'shown' to your PV7 for your cartridge.

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I put copies of the research I did about SUTs as one of my Virtual Systems.

Click on my name, choose 'details', it will take you to a page with a list of Virtual Systems, one is named 'SUT info'. One column shows the xFactors.

Small print of scanned pages: temporarily change your monitor' ZOOM from 100% to 150%s. Put back to where it was, i.e. 100%. 

An xFactor of 12 would be good.

.35 signal x 12 = 4.2 mv, a very good signal strength for MM Phono Inputs.

xFactor 12 results in an impedance of 326 'shown to your PV7, very close to recommended 330 ohms

Where is the OP going to find a SUT with a 1:12 step up ratio? If such a one exists off the shelf, it might be unique. Whereas there’s a plethora of choices among 1:10 SUTs.

Nad used to make inexpensive electronic pre-phono box that boosts necessary gain pretty much for any cartridge.   Classe Audio NIL is probably higher priced pre-preamp.