Here is a link to the RCW setting excise rates: https://app.leg.wa.gov/RCW/default.aspx?cite=82.27.020.

Using the rate of .0525 the excise (landing fee) would be $26,250 on the low value estimate of $500K and $31,500 on $600,000 value which covers the range estimated in this thread.

In my opinion the rate is too low but the bigger issue is that the excise tax goes to the general fund.
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