Well,
It's almost 3am and I scanned the whole article and loaded it here:
http://www.pihakaetta.com/info.php
It is entitled: Sinhala Weapons and Armor and it is a VERY big PDF, so I recommend right-clicking and saving if you don't want to drag your browser down too badly.
Also, it was sanned from copies made previously. It's very readable, but it ain't pretty.
It is a fascinating article with some insights on all aspects of Ceylonese weaponry, but there are some especially interesting explanations of pihiyas. Once again, there is evidence to suggest that the term piha kaetta is erroneously applied to all these knives.
going to sleep now......
-d