Hehe, yeah, and my butters 211 is rated at 8mm .
Manufacturers rated specs don't mean much in the real world I'm afraid, I learnt that the expensive way .
Not sure you can get 0.9mm wire other than gasless stuff, the common smaller sizes are 0.6, 0.8, 1.0 and 1.2mm. I'm sure you'd be able to get a suitable roller for 1.0 though you shouldn't really need it on 3mm steel, handy to have one though just in case. send weldequip a PM, he's a Clarke dealer and might have one in stock or would at least know if one is available.