I couldn't see it listed as being able to buy in the Line 6 replacement part store and when I looked at the switches stocked by Maplins (electronics supplier) they seem to be of a lower rating than the HD147 switch (a Chily 6011 20A 125AC and 10A 250VAC).

Or would something like this do the job? http://www.maplin.co.uk/Module.aspx?ModuleNo=2360