Through the years I’ve serviced many many heads that had been running fine with the tip heights varying by as much as the OP’s heads.
The one head where they vary .015-.030........it’s not great, but also not worth spending a pile of $$$ on correcting it either imo.
I’d work on getting the other head with the bigger tip height discrepancy so it’s in that same .015-.030 range and call it good.
Then I’d find some exhaust rockers that are longer than the 273 rockers(as in, correct length w2 ex rockers).