Well, in that case, a few truths apply;
Buying expensive Jap brand name clutches for low power RB20s doesn't make sense.
Most people on SAU are in Australia, therefor most of us would recommend an Extreme or NPC or one of several other local clutch assemblers. These are all Australian businesses, so it would make no sense to recommend one of them to you.
Therefore you are reduced to waiting for someone in the US to make a similar recommendation on a clutch supplier in the states that they trust to build good clutches for Jap cars......or you widen your search parameters (away from Skyline specific info sources) and just look at who recommends what shops in the US for similar applications.