Sure, try

:if finfo('myfile',61) > 0 then

or, for better readability,

:if finfo('myfile','accessors') > 0 then

or even

:if finfo('myfile','num accessors') > 0 then

:HELP FINFO will display a list of available options including both the numeric option code and alphanumeric alias. Unfortunately, the HELP text sometimes lags behind the implementation of various options. Therefore, it is always a good idea to have recent Communicators available. New CI options are almost always documented in the Communicators.