Can you run the HANA SL MC at 100 ohms?

I think the op means he is using a SUT with 1:10 ratio and 47k on the secondary, which means cartridge sees 470 ohms.

Loading is entirely for the benefit of the preamp not the cartridge. Here's how it works:
The cartridge is an inductor. The tone arm cable has a capacitance. Since they are in parallel, the result is a tuned resonant circuit, often active at +100KHz frequencies or even into the MHz range.
If your preamp isn't happy with radio frequency energy coming in (and that is what I'm talking about) then the loading is used to detune the resonance and thus kill the RFI (Radio Frequency Interference).

It is therefore non-critical- a low enough resistance value is all that's needed if your preamp can't handle RFI (and if it has a switch for loading on the front panel then that is the case).

I would try it without any loading and see how it sounds though! The load causes the cartridge to do more work and thus makes the cantilever more stiff and less able to trace higher frequencies.

Lewm is correct in his post, sorry for any confusion.

I moved the turntable (Clearaudio Emotion) I have my Hana SL mounted on to a secondary system and am using a Parks Puffin which only has a 200 ohms setting and it sounds great there.  No experience at 100 ohms.

^^ Good. The highest load you can run without problems is the best load.