ghandou, I disagree with the previous respondees to your post and, like you, believe that it doesn't matter how much you get paid if you really don't like your job. I'm not totally sure what an oil contractor does but I'm fairly certain I'd take my current job as an FO over the job, T&Cs and location that you describe. Most of us love it, despite what you read on here (at least in my airline). Whatever floats your boat of course, some people will do anything for money.
To try to answer your question: it really depends on where you end up, but 10 years in a company on a jet and you should have a command. Including flight pay etc you might be looking at around £100k gross (or just short of) in a Lo-Co, a bit more in a 'flag carrier'. There are a few variables of course, but that's 'ball park' and in today's terms.