That'd be the M-504 (see my pictures) and the 506/508/509/510.
The 504 and 508 had the same meters. The 506 and 509's used different meters yet. The Grand Integra 510, well, if you find one of those, I hope your credit rating is solid.
The setup looks fantastic Mikey. What kind of binding posts does that amp of yours have on the back?