I'd just use an alias as mentioned...
alias RepB {
return $replacex($1-,[,ÿ,],Ö,ÿ,[,Ö,])
}
Then, when writing to reading from the INI file, use:
writeini file.ini section $RepB(item) data
$RepB($readini(file.ini,section,$RepB(item)))
Example:
writeini file.ini section $RepB([my_item]) data
$RepB($readini(file.ini,section,$RepB([my_item])))
Note that you can change the characters that are being replaced to something else if you like. I just picked a couple random characters that probably won't be used in your INI files.