I'm not understanding why you couldn't buy the Giant Defy 0 and take it to Hooked On Cycling for a fitting like you did the last bike?
Just take the measurements from the bike itself - just as easy.
Saddle height from centre of BB to top of saddle (+/- any difference in crank length)
Saddle setback from bottom bracket to saddle nose
Reach to Hoods from saddle tip
Top tube length ctr to ctr
Drop from saddle to hoods
Stem length
Top tube length
Assuming the frame geo is not massively different from one bike to another, that should get you in the ballpark.