Which Breather…?

[Brass]

I'm currently using an open system with a pcv on one side and a breather/filler cap on the other.  The stock valve covers have the 1.5" diameter neck.  The push-on breather cap I have now causes a lot of blow-by.     I want to get a K&N style breather that should help with that -but I haven't found any I'm confident will fit the stock valve cover.  Does anyone have a part number I can plug into Summit's site that will work - or do I have to get different covers?

Thanks!