I would look for another complete balance assembly, then find jewels to match. I have done this on several American PW's, and it usually turns out just fine. Your approach here seems like an awful lot of work, and would make me want to set this job aside, and move on to something far less fussy.That's why it's a hobby. I like being able to take my time to do things right as opposed to right now. The pain with this roller table has me wondering if I should just be on the hunt for a complete roller table with jewel instead of trying to monkey the roller jewel into this pig.
A number of American PW's used parts that were ( and are ) amazingly interchangeable...you might be surprised! That was their 'claim to fame' back in the late 1800's, and they got very good at it.