I'm not familiar with a Lemo RTA, but FastTech sells many different pre-wound coils, in a variety of wire types, many different ohms of resistance, and inside diameters. They're also very inexpensive, too, at about $3.46-$5.00/pack of 100. You just need to decide whether you want Kanthal, SS, etc.; the ohms you want; and choose a diameter that will definitely fit in the coil space in your Lemo. I buy my pre-wound coils from there, for my KFL+ shorty tanks and my Berserker RTAs.
There are some US vendors who also sell them, though the cost is considerly higher, and I've never seen one that has the variety that FastTech does.