The casing looks umarked
[Linked Image from i3.photobucket.com]

As for the valves, well I can't tell as I haven't seen that many mower set ups
[Linked Image from i3.photobucket.com]

I wish the mower had an hour meter to give some indication. I really think it is a low hour unit. Tyres, blades, belts etc seemed to be original and in suprisingly good condition.