Truth Hardware universal joint

I'm afraid not. All Truth operator parts are only designed to fit an 11/32" spline. There isn't really any wiggle room when it comes to that measurement. 

The term "universal" for our 39-338 is a bit of a misnomer. What this means is that it's universal for Truth windows, not operators in general or non-Truth hardware. I apologize for the confusion. I'm afraid we don't have a corresponding part for 5/16" splines.