The Ferrea valves will come fully backcut, margined, swirl polished, etc. So they will be straight drop in (the machinst should in theory check the angles and the roundness before installation... but it isn't absoluteyl necessary, just a good thing to do).
A full set of the Ferrea's I should be able to sell at about 625. Lesser alloy's and high enough volume and that price can be cut down a long way. That is the intake and exhaust... if you just want one side it'd be half that price.
I was surprised to see my valves as fried as they were becaus everyone always thought my EGT's were super low as I considered it to be "high" when I crossed 750C and other people were running well past 850C.