I would take the sachets instead, I took mine on a trans-atlantic flight (having checked with the airline and the destinations high commission too - but then, I was taking 65 packs with me!).
I also took bars, but in my hold luggage. You should be absolutely fine taking the packs in your hand luggage as they are sealed and you don't need to put them in the clear plastic bag either as they aren't liquids.
Worth thinking about though, is taking your own clear bag as, when I flew from Luton to Dublin I had to BUY bags at the airport! Grrr.. they must be of a certain size and sealable when filled.
Hope this is helpful, worth calling the airline if you have time just to double check, (I'd be sorely tempted to shove the bars in the bottom of my handbag and take packs too) lol
If you don't have any packs perhaps a nearby CDC could sell you some, or a friendly nearby dieter might have some to spare that you can buy? Just a thought...
Safe and happy travels to you x