Taken from the FN-HerstalWebsite:
TM is a 1:1 replica of it, so dimensions shouldn't be that different. However the height is probably less than 210mm as this is, I think, for the RD, not the TR Version. Hope that helps!
Loving the pics of the P90's, I'll nick my mates camera and get a few pics of my P90RD without the RD.
EDIT:
Oh! Just found the P90 Tactical, (P90 TR)
Both lengths are without the silencer.