Tom,
I found two pieces of info which may simplify the task of those like you who use green tea extract (mainly for its EGCG) & want to improve bioavailability.
The first one is a supplier of 10g chocolate pieces laced with 100mg of 90% pure EGCG. If this purity is adequate it might replace the home made chocolate confection described in a link provided in a previous post in this thread:
http://www.neuchatelchocolates.com/EGCG.asp
The second one is about one supplier of 94% pure EGCG at a reasonable price:
Teavigo™ made by Pure Encapsulation.(60 veg-caps, each 150mg of which 94% is EGCG)
These pills are much more affordable than the higher purity chemicals available from suppliers like Sigma-Aldrich whose prices run in hundreds of dollars for a 100mg single quantity.