APU2C4 Jetway NF9HG-2930 if this might be not really strong enough!Is this going to be too much for the APU 1D?
But the best way in my eyes is to insert a small Layer3 Switch such as the following
A D-Link DGS-1510 or Cisco SG350, they will route between the VLANs if this is needed with wire speed
if not needed you can also go with a Cisco SG220 switch, that is really fast and wicked. then the APU1D
would be enough for it or one from the both other named above boxes.