WIW? - M/T Finned Valve Cover Breathers

[PxTx]

Without a picture, I would value them at about $200 in the high side for the pair. I'm sure there will be plenty who can say how they can be had for less, but clean examples are getting hard to find.

The one limiting factor with those, which does narrow the market is that they require a destructive install. Meaning you have once they are installed, if you remove them, there are holees and such left behind that don't look so good.