Mine has a rubber fuel pipe between the mechanical fuel pump on the RHS of the engine and the front carb fuel inlet, secured with a metal loop off the front of the head/engine stay bar.
I cut the pipe and fitted a small paper type filter about half way along, easily visible to see if it starts to block.It catches far more than the mechanical pump's gauze type.
I got mine from a family run vehicle parts shop, would have though halfrauds do something suitable.
Regards,
Adrian