Ok, thanks for those who replied, you should see the money in your account tomorrow... I will be out of the country on business for the next week or so.
We have all brought second hands cars and parts and discovered they are not what we thought they would be soon after buying, you need to ask yourself if you paid a fair price for said goods and question if what you have been sold is of a safe and of reasonable quality.
If you have been genuinely duped and the vendor is non responsive or is being unreasonable, I recommend contacting the commerce commission, if said vendor is running a business he will at-least have the chance to defend himself in front of a non bias.
I hope both parties involved sort it out.