I would say it's a good price - they tend to resell for close to their original retail price (i.e. they don't depreciate in £ terms, just in real terms). The L3 is the old model though, and its M-shaped bars will probably mean they're higher than the saddle.
The telescopic seatpost is heavy (even if it's titanium, which is unlikely) and you'd be better off with a standard or "extended" plain post.