Holley 1920 R-4003B, 4162

I've got this old thing and I'm brushing off the dust to see if I can get it going. However, I've been searching around for a rebuild kit and I'm coming out without any luck. Does anyone know where I can find a build kit similar to this model? I'm having a tough time locating one. I'm pretty green to this sort of thing so recommendations are appreciated. Mike's Carbs doesn't list this model.