Hi Nicola,
My name is Jamie Lewis (no relation, I guess?!). I've just completed a contract with a Swedish native advertising firm and I'm absolutely certain I can get higher quality traffic to your site than with SEO.
I optimise adverts in Facebook to a hugely proficient degree, targeting audiences based on previous conversions. So, in essence, we can display ads to people that are a) demographically similar to your previous paying clients and b) likely to click through to a purchase.
If, however, you'd prefer to focus on registrations, then we can tune the audience to reach that goal, too.
I'd love to have the opportunity to explain this to you in more depth.
Thanks for your time,
Jamie Lewis