There is a known option: Get the leavers and joiners and then build the history of constituents from there.
However, the history of leavers and joiners is not available for data former Aug-2009.
I believe that the index existed before 2009, once there is the history of prices from november of 2000.
Is there a better place where I should place this question?
The index "ticker" that I use to find it in desktop Reuters is "TRXFLDUSP".
I believe that the data is available up to 2009-08-03, please see this sample result:
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