No, spry does not have a way to offer validation for ether a us5 or us9 zip codes.
you could add a second text box to the form though, and set it to numeric validation. set the min value to 1000 and the max value to 9999, this text box can be used for the user to enter the last 4 of the zip if they wish to use the 9 digit zip code.
for more details on configuring different spry validation types:
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