Seperate phono stage v.s. step up transformer


Fellow analog lovers help me with this dilemma. I have a Teres 265 turntable with a Graham 2.2 arm and a Lyra Helikon cartirdge. I just purchased a new preamp that has a terrific phono stage but, its' sensitivity is 2mV @47Kohms and the Lyra cartridge is only 0.22mV.
So I have 3 choices, get a new cartridge, get a seperate phono stage, or a step up transformer.
What would those of you with more experience in these things do? If it is change cartridge, which one? If seperate phono stage, which one? If a step up transformer can be used without sacrificing any detail, dynamics, etc. which one?
Thanks ahead of time to any of you that answer these questions.
agaffer
Check www.bentaudio.com - the S&B step-ups are about as good as it gets, and his prices for the Mu step ups in either kit or prebuilt form is a helluva deal.

-Ed
Thank you for your responses. The preamp that I am refering to is the Granite Audio Model 770. Their CD player with the tube output has been the first CD player that I have owned that I can listen to with as much enjoyment as vinyl so, decided to try their pre-amp also. Before I was using a ARC LS 5III with the Phenomena + Battery pack for a phono stage. Not the best phono stage but, I got it as a package deal with a used Clearaudio turntable before the Teres.
The Granite preamp can be returned after 30 days and I could go back to the ARC but, I like the Granite better. Just have to figure out if I should change the cartridge or go with the step up.
Yeah, go with the TX103 from www.bentaudio.com. Buy the kit version and save. Best trannies on the market today. I use them with my Trumpet.

jh
I have gone through something quite similar recently with a built in phono stage in my nuvista and scoured all over for information. I got a large amount of input from people here and on aa. I believe everything people have said thus far is more than reasonable. The input I had was that bent audio make great stuff. For a simpleton like me I understand it that transformers will allow you to boost the signal and are a very economical way to go. If you don't care for the improvement they are generally easy to sell. I ultimately went with a separate stage and this has had an amazing improvement on the quality of musical reproduction. Since I struggled with this for some time drop me a note if you wish to hear the sordid details. Good luck