Is there a list of double pay transactions somewhere?
I had most of my coins invested in shares and received a <1 BTC transaction that was my recent dividends from before the shutdown.
Even though it is a small amount I would like to return this if it was double payed, but I really have no clue what my balance was at shutdown.
If you had gotten a double payment then you would have gotten 2 transactions with the exact same amount. You sound like you got only one payment so you arent one of them.
Not exactly true, in the first round of payments GLBSE sent multiple amounts to the same user. It does not come as one single amount. I got two payments from GLBSE for the same amount but that was because they divided my claim into two payments.