Hi Grifone, thank you very much for the in depth reply. For me, very informative. There are no tyres on it, the wheels seem to made from some "Mazac" type material. The crosshead, I think, is cast and the cylinders are black with orange lining, so I assume "Montrose". It is the "horseshoe" magnet and seems to fit the 39mm coarse thread armature.
Regards