I wonder what seashell looks like in pink! Being serious for a second, there's no need to buy fins if you don't want to carry them as you'll certainly find good enough to rent. Though Scubapro make some rather nice short & light ones.

As to the snorkel, maybe get your own for hygene reasons and to ensure you have a good and durable fit to your mask. Get the simplest you can - no purge valve or flexible section, just a bent tube. Works best in the long run, is cheapest, smallest and lightest.

But certainly get your own mask. I see so many people whose holiday is spoiled by a mask that doesn't fit properly and leaks. Again, the simplest the better (no purge valve), and make sure the bottom of the mask is well clear of your upper lip when you try it on.

I do sell some of this stuff in my shop in town, though not the simple snorkels that I prefer. A good quality scuba mask (which is toughened glass, not necessary for snorkelling tho' better) should cost no more than around US$50.