I would take the museum's advice on buying that flag.
To order a US or California flag that has been flown over the State Capitol, please call Senate Publications and Flags at 916-651-1538. The online order form can be found at https://spub.senate.ca.gov/.
I'm not too sure, but your best bet would be to ask in the gift shop or ask in the visitor center! -Miguel
I'm sure it is. Unfortunately I couldn't tell you how to go about it.
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