Well it's going to be cheaper than the can I got from the vet I had to call out, but there you go.
It's helpful if you feed-back what your experience is with the online vet (and give a name) because it's always a step in the dark to try out a new supplier. I buy everything on-line and price and service is hugely variable, so I tend to stick to the same people who supply good stuff at reasonable prices.
So following my own suggestion I can completely recommend Paddock Perfection on eBay for electric fencing stuff. It is all exceptionally high quality (horizont) stuff and delivery is fast. I've spent the last year replacing all the crap kit that the local farmer installed to get me started but where the plastic is breaking down or he just knotted the tape rather than just using proper joiners.