That's true, but you'll still get a fair few of them through bonus stage and GHQ, so might as well not max the limited types first so you don't get gold instead.
Would it be a good idea if I stick to 5-3 fo a while when I reach it? According to another topic is has similar drops to 1-3. Now I'm sure I wont reach rank 1000, might as well prepare fo the next event.