302 head , stock valve spring ?

Something I got at a swap meet. Was raining hard , the guy was cold and wet. got used cam/ lifters/roller chain and gears/ with adjustable rocker arms and shafts all used $15.00 how do you say NO ?
The guy said (as I remember it was a mopar cam 759 maybe/ I don't know any more) but it was not big enough for his 340 duster....a good day to be at the rainy swap meet....just wish I could remember.