How to choose step up transformers?

I just get into vinyl.  I bought a Sony PS2250 turntable and I have a Luxkit a3300 preamp.  The preamp has a MM phono stage but not MC.  I would like to get a MC cartridge so I am looking to buy a Step up transformer.  I don’t know what MC cartridge I am going to get yet.  Do I need to match up the cartridge and the SUT?  If yes, what do I need to match?  Likely I will buy something not too expensive such as the Denon DL301.