You can not damage your cartridge with 47k Ohm loading, use it if you like it, absolutely no harm for the cartridge. We have many audiogonners who preferred 47k Ohm for LOMC cartridges. So you can use MM input (47k Ohm) for your MC cart.
As for the MC input i think you can change GAIN setting on PH-10 ?
As for the MC input i think you can change GAIN setting on PH-10 ?