While the proposed changes will level the playing field, putting all companies in all industries at the same permitted exposure level, it is hard to say exactly how much it will cost. And, there are a bunch of regulations that go along with it for testing, and education and regular medical examinations, etc. that will further increase the price.
Here is a link to some great information about the OSHA silica proposal. I would urge you to get informed.
Of course, some will say a safe fabricator is a happy one and silicosis is a horrible affliction, and that's okay too. But time to weigh in with an opinion is running out. The debate on the proposal opens on March 18 with the deadline extended to April 1, 2014, and you can find more info at http://www.regulations.gov. Also, post-debate comments may be made up to 45 days after the deadline, so there is plenty of opportunity to get your voice heard on the matter.