So, despite the fact that I actually like this store and will shop there again, I decided to see what I could come up with by way of a do-it-yourself romance kit (I blurred the store name on the product above, which is why it looks a bit strange--an artist I'm not).
First of all, the box. Although I like the little tin (not sure of its size), I'm sure I could easily dress up a cardboard box or basket or gift bag I already own, the advantage being (other than the cost savings) that I could totally personalize it. What's more romantic than something a person took the time to make with their loved one in mind?
As for the rest, again to keep the cost down, I've concentrated on dollar store buys. Candles of various types (scented, unscented, colorless, colored, tealight, votive...) were available in sets of at least 4 for $1. These (below) are unscented (I get headaches from too much artificial scent). If you really want scent, you can buy the scented candles, buy incense and a holder (also available at the dollar store--40 sticks of incense!) or make your own scent. There are some good ideas at this website.
As for rose petals, I found this package of 300 (also available in red or white) for one dollar at...well, you know where.
With the money you've already saved on the basic ingredients, you can embellish a bit. Add some chocolates. If you like wine, you might include some wine glasses (maybe add some decorative wash-off messages on the glasses)?
Cut out some hearts from colored paper and write notes on them, scattering them in the box/basket/bag. Or make a trail of them through the house, leading to the basket. Include some romantic music you already own in the box (no one said it all had to be new, just romantic). If you're not good at cutting hearts, here are some cute sticky notes with hearts on them (yes, they're from the dollar store). Or make your own, decorating sticky notes you already own.
So no, there's nothing fancy here. You can embellish this as much as you like or as little as you like. But at least you'll have more than six rose petals.
Have fun with this!