What Rocker Arms Are These?

Those Hughes ones aren't made by (or for) Hughes. They're just the standard PRW stainless rockers - still good rockers in my opinion. I've got them on my 340. They're very different from these ones though. They're bushed with cup-style adjusters and just look different.

I think I've figured it out though. Pretty sure these ones are the old-style Comp "magnum" rockers (#1420)

Here's an old thread all about them: Roller Rockers Geometry