Just a quick update note to say thanks all for the kind help, battery charged to full and bike started first time.

1.5 months until i can legally ride it!
possibly a bit longer until i can _actually_ ride it with confidence though!

For reference, i ended up with the Optimate that Gina referred too (UK based and next day delivery sinched it), worked fine and looks like a reasonable bit of kit.

Thanks again all, both for the advice and encouragement.

Anthony