Chains

[MRail]

That sounds correct...
Just (crudely) measured Slo-mo chain on Stanley.
Pitch is a little under 4mm or 1/8th inch, 0.125".
[attachment=0]Chain.jpg[/attachment]

[Busted Bricks]

At £71.82 for 300mm the 4mm pitch chain is a bit on the expensive side. About 12 times more than 03C-1. Of course if you need it, you need it.

[DonW]

Perhaps a large component of the Slo Mo price. But for a commercial loco the cost could be bearable.
Don