Just by model designation, I'd expect Enkei Tuning to be cheaper and heavier than Enkei Racing models.
Tire Rack describes each wheel's weight so you can use the link above for this wheel, then change the brand from Enkei Tuning to Enkei Racing, to get the weight of the RP wheel, which is likely to be a bit lighter again.
There are probably a few options for light wheels but few lighter than what you have now.
I suppose weight is less important if you just want some wheels for the street and to give the car a different look. Let's see if there are pics of these wheels on a car like yours.
