The closest places I can recommend is either Somers machine in Vancouver, WA or Southworth LLC in Eugene, OR
Talk to Archie Somers at 360-699-5205 and or Carl or Don at Southworth at 541-431-0556.
Call them both and let them know what your doing and see which one you like the best or the least
Tell them I (Cab) recommended them to you
If they don't tell you what you want to hear then try Valley head Services in Northridge,CA at 818-993-7000
Larry Ofria is the owner and he has been in business for 30+ Yrs specializing in Hi Po head and engine work for racing.
I use to race a 1963 Plymouth M.W. car in NHRA stock, I had to learn who was good on machine work, trannys, converters and every thing else in that car and who wasn't worth doing business with
I wish I knew a good NHRA stock 440 class racer to send you to for your head work but I haven't race NHRA stock since 1988, the proper valves (that will check legal)can make as much as 20 HP more over a not so good replacement set
Good luck on this, to outrun the fastest cars in your class you need as good as or better parts that they have and you have to work harder and smarter to out run them
It won't be easy, cheap or quick to occur, DANG IT
Good luck, go get them