Speak to your DO.
It has been done before...but not often.
The needs of the service come first so now that you are required to complete a ROS for the training that you have received you might find that a difficult hurdle to surmount.
You need to be really really fit, particularly upper body. I think the PTIs can advise with this. You need to prove that you are fit before you can transfer, not just RN fit, but RM fit. You might be able to get a visit or acquaintance type thing to find out more.
Speak to your DO.