There's not a lot of them around anymore but they can be found, Williams made a ghost ring rear sight that bolts onto a TC. There are two different bolt spacings though, so be aware and check what you have, the Williams will only bolt up to one of them.
I didn't like how wide the front post was either, I found a set of Williams fiber optic ghost ring sights and put them on my renegade about a year ago. My only complaint about them is the front sight is still too big for my liking. I'm going to mess around with trying to paint it to about half the size with some of the wife's finger nail polish and see if that works.
Even with a 6 o'clock sight in it's still just too big of a reference at 100 yards...heck at 50 yards. It is twice the size of the POA at 50 yards, let alone 100.
On my bow sight I have .010" pins, I love them. I've thought about trying to convert my new FO sight on the renegade over to that size. Put some kind of shim under the .010" FO so it's at the top of the sight? Might work...