These bracelets used to be an annual release in late spring in the States, from approximately 2007 to 2009. A few different versions were produced, including an interlocking set of two as well as one set with a melee diamond.
The closest item to that bracelet that Cartier still sells is the silk cord Trinity. I have that item and use it as a "buffer bracelet" or string it on a neck chain. It's nice by its own standard but it's not a particularly good substitute for the Love charity.
I recall that the single, plain one introduced in 2007 retailed in the ballpark of $425 - $475, which was a substantial markup at the time (gold was much less expensive then). The last one produced was rose gold with a diamond and retailed in the $700 range.
Your only choice now is to go through a reseller, but from what I've seen they add a ridiculous markup due to relative scarcity. There are also many fakes, so beware.
Curiously, I believe that the 2007 run did not come with certificates. Subsequent runs did, I believe. The silk Trinity does come with it now. Authentic Cartier items without certificates are common (they get lost), but a plain yellow gold Love charity should *not* come with a certificate.
I hope this helps and I wish you well in finding an authentic one at reasonable cost. For what it's worth, I think you're better off looking for something else for the money you might pay for one today.