I can tell you what i can see from the pics....
It is hard for me to tell from these pics..maybe you could post a few more.....but this looks original to me...but if you could post a few closer pics of underneath the top plate on the machined surfaces where the 2 manifolds bolt together...also, the side edges of the top plate between the intake bolt holes...I own one repro xram(just for comparison) but, I have not yet seen the heartbeat city repro, but the repro top plate I have has the date code in a different location than all the originals...
so..based on what I see so far...
if you can post some close ups...I can give you a better idea...