Here's one that I'm looking at , at Kingfisher
It's $165....here's the description
The Yagyu bokken is a sword of finesse and evasion. The techniques of the Yagyu Ryu involve moving into positions quickly and lightly. This wooden sword is very thin and fast and not oriented to influencing the path of another weapon through heavy contact.
Looks very nice...not sure if it's appropriate for Aikido though.