There's another similar questionanother similar question and bindfs is suggested there:
mkdir /home/$user/sda1 bindfs -u $user -g $group /mnt/sda1 /home/$user/sda1 OSX users suggest noowners mount option described like this:
Ignore the ownership field for the entire volume. This causes all objects to appear as owned by user ID 99 and group ID 99. User ID 99 is interpreted as the current effective user ID, while group ID 99 is used directly and translates to ``unknown''.