...along with standard pressure at other altitudes (which I'm afraid I don't have to hand).
Dredged up from 50 yrs ago, rule of thumb we used to use to read the met. charts - 300 mb = 30,000'
400 mb = 24,000' 500 mb = 18,000 - I think.
It was only a guide, anyway, invariably the actual conditions encountered would be different, like headwind out, headwind home - that's Met. for you.