Hello Geoff,
a pic is always nice for identification, the number you gave me I do not find in the professional audio catalog, does not mean it doesn't exist, can be a custom model, a Klangfilm designation, etc.
All grey series (V7x,W9x) have a sticker with a 6S ELA with four digits attached, the transistor units have C,D or E number with a min. of numbers after it... Or the F (factory number) works same as good for identification...
Best