There is no need to change your fork oil every year - especially with those low miles. I changed the fork oil for the first time on my Softail Deuce around 10k miles. I used the regular Harley fork oil. I wish I would have went a little heavier though.
I have a 2006 FXD and the fork tubes have to be inverted to drain the oil out. So, I only change the fork oil when I have to take the front wheel off like changing a tire. I think the book on mine says every 20,000 miles.