[Coley]

If you are going to 'stick' with old school iron heads then you might luck out and find a set of either '041' heads or '186' heads.
These are original late 60's to 1970 series sbc heads and are very well suited for these truck engines because they have the needed accessory mount holes....but provide higher compression (64cc chamber) and still have the other needed attributes.
They are good heads, definitely better than 624' or 882' heads.......although not as good as new tech heads.
(note: these heads were found on the 300hp/350's of the 1969 and 1970 typical of camaro's, caprice, chevelle's, etc....for general reference sake....they were definitely not on the truck engines tho', which used a lower compression head with a 76cc chamber).
They will flow well and they will kick up your power....but again, the newest heads will outperform them but it all comes down to what you are expecting and what you need vs what you want......and of course,....what you are willing to spend to get there.

However,....you will have to look around for a good set and if you are very, very lucky you will find a good set for a few hundred bucks somewhere that you can 'bolt and go'.
If you do find a set, perhaps on an older caprice?....in good shape...then try to stick with 1.94 valves which will give you better torque characteristics than the 2.02 ones....noting that both valve sizes were available in those heads)
However, if you get into a set that requires work and renewal....you will be pushing $800 and might be better off just buying a brand new set somewhere.

my two bits.
Coley