What's your budget?
Expected downtime?
Care about originality?
If you answer: not unlimited, low, and not really, then I suggest finding another head, (E21 works if you have flat top pistons), having it rebuilt, then swapping it out.
If you're not rebuilding the bottom end for higher compression, then there's no point in going crazy with the head, but plan on replacing almost everything - springs/rockers/eccentrics/shafts/etc (peace of mind is worth it)
When I had mine rebuilt, the machinist noted the valves were quite worn, so I had to buy new ones, the IE stainless valves were cheaper than stock replacements (same size). Also added the single spring HD valves and chromoly retainers (cheap insurance)
Alternatively, find a good used head, plop it on, and rebuild the original.