I believe that this is possible, although not trivial to do with Applescript using Pages built in Applescript dictionary. It depends on exactly what sort of functionality / formatting etc. you need.
The following script might be a good starting point. In this case it searches for pages with the word "member" but you could change this to a dialogue, a list or whatever you found useful. The code is a little crude and not particularly quick but it does work.
set theSearchText to "member"
copy theSearchText to theOutputText
set theOutputText to theOutputText & " "
set theCurrentPage to 0
tell application "Pages"
tell document 1
repeat with i from 1 to count of words
set theText to text of word i
if item 1 of theText is equal to "member" then
set thePageNumber to the page number of the containing page of word i
if thePageNumber is not equal to theCurrentPage then
copy thePageNumber to theCurrentPage
set theOutputText to theOutputText & ", " & thePageNumber as string
end if
end if
end repeat
return theOutputText
end tell
end tell