Valves are only one third of the equation. You also need to have properly-fitting valve guides, and the correct position and width of the valve seats. You'll also need to get the head magnafluxed to check for cracks. Doing a shade tree job after buying a whole set of valves would be a really bad decision. Bite the bullet and let a good machine shop do their thing.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!