There is a huge difference in volume when it comes to different MRI machines. The older models are incredibly loud and then there are new ones with >30 dB less noise. If you need to take MRI, I'd suggest insisting on getting it with machine that is as quiet as possible.
I should go take one in the upcoming months as well, but it's been really hard to get any kind of information from the public healthcare, when it comes to the actual decibels the machine chosen produces. I am considering private health care now, since they supposedly have quieter options - it's just damned expensive.
The risk of getting worse tinnitus from MRI is terrifying... I can't imagine the amount of regret if I chose to go there and then come out more damaged. The volume can peak at 120 dB and that would be way too much for me, even with earplugs. My tinnitus is still at a very vulnerable stage and even >70 decibels can flare it up at times. The last spike (perhaps permanent one at that, since it's been over a month) I got was from going to see the latest Star Wars movie and I wore a good pair of earplugs!
So I really don't think my ears can handle noise right now, it's really a tricky situation. I am not even sure why I got an invitation to MRI, since my tinnitus was clearly triggered by acoustic trauma and isn't unilateral.