Kyo, i'll be honest with you.
Haks is probably not the guy to go to do this. The last time I spoke with him, he didnt have the tool, and this was less than a year ago. I wanted to go to him, cause of his status as the exhaust expert, I thought he'd have the right tools, but he didnt.
Haks does really really good custom work, and his prices were pretty competitive (heard it's gone up though, cause he's so busy?). But if you are looking to fit a mid pipe which is straight bolt on (i.e. no custom welding or bending etc) then any mechanic with a hoist can do it. If he was the one who quoted you $70, I think once he gets it on, and sees you have to cut stuff and take off the extra cross member, then he will probably up the price.
A local mechanic will be happy for the business and do a pretty much the same job. Just make sure they have gasket seal paste. It will probably cost less.
Not taking anything away from haks, cause he does brilliant welding, but this doesn't require his custom work expertise.
Kyo, if you are who I think you are. You live in rhodes, and there are plenty of mechanics on victoria rd and in regents park area. Both of which are much closer for you.