It depends on which 16613 you had- Some of the older Chinese Subs had the standard ETA placement for the date, and in that case, a gen dial would not fit correctly, as the date window would be offset from the datewheel. Most Submariner reps have what's called a 'date overlay' on the existing ETA datewheel; this is a thin disc with the dates printed on it that sits on top of the ETA datewheel and repositions the actual date to the same location as the genuine 3135's date (the genuine date window is more inboard towards the center of the dial). In this case, a gen dial should work, but you'll have to remove the dial feet and secure via dial dots, or you may be able to source a watchmaker with the ability to relocate the dial feet (the most ideal solution).
It should be noted that the datewheel overlay adds additional height to the ETA datewheel, and there is very little clearance under the dial. The common problem is that the datewheel will likely rub or come into contact with the dial, and the end result will be a date that does not flip over completely or at all in some cases. As rosnik mentions, it's a good idea to get someone familiar with this process to do the work for you, as there will be a lot of trial and error with getting everything to work right (speaking from 1st hand experience).
Good luck!
//ubi