I do not think there have been any TVs at that size with a 120hz panel, ever, let alone on your TV.
I think though since you are a fan of motion interpolation like trumotion you should really aim at getting a TV with a 120hz panel instead, you will notice a big difference and its worth saving the extra for. The native panel refresh rate is more important than the fake refresh rate manufacturers quote and will give you much better motion overall when using enhancements.
If you can go up to 49" instead of 43" there are some better options too, you get the LG 49SK8500, Philips 8 series, Sony XF85/87 series and the Panasonic FX750 all using a 120hz refresh rate at that size. Even the Sony XF85/XF87 is a better buy at this size than 43" because it uses a VA panel instead of IPS. The other mentioned models are all using IPS panels like your current TV.
Sticking only to 43" and you only have one choice in the Sony XF83/XF85 series which unfortunately is an IPS panel only.
I refer to 120hz instead of 100hz btw because every 100hz TV is actually 120hz, its just they use 100hz to describe the refresh rate in Europe due to broadcast TV being 1/2 or 1/4 the frame rate of that.
The holy grail would be 49" and the Sony XF85/XF87 but if you cannot fit, the Sony at 43" is a good TV too. These are probably the TVs I would go for if I couldn't go up to 55". Not only are they using 120hz panels but they also have very good motion processing, more highly regarded than the competition.