I found for 877 with the return stopping in ORD which is short 1700 miles
Short 1700, or 1700x3 ?
If only short 1700 Aegean miles, you will only have to also MR something like NYC-MCO in a class that credits 1=1 to Aegean (V or higher on UA). I guess you could also do something like NYC-SAN (usually has decent deals) in G class or higher earning 1 = .5
LGA-IAH-SEA-IAH-LGA in A will get you 6581mi which is greater than the 6334 needed (x3 + 1000 signup bonus).
PHL-IAH-SEA-IAH-PHL in A makes the cut at 6397 but the fares are significantly higher.