You Gentlemen might be interested in checking out what's listed at MidwayUSA - much, MUCH easier to navigate that site than the poorly organized Brownell's site in my opinion!
At MidwayUSA's, I find it is easy to look at various front and rear sight parts from William's and Marble's especially!
When deciding what you want your "open" or peep-sights to look like, and their heights, sometimes its a matter of choosing two or three parts to achieve that goal - for example, if one wants a from blade sight .470 or .500 inches high.
It may be possible to buy a one-piece front fiber-optic front sight that is .470 inches high, but if one doesn't like a certain style-choice of the height is wrong, any number of "combinations" are possible to choose and match and fit together.
To achieve that .470in high front sight one might find a fiber-optic sight like that, or one with a brass bead or white bead. Or to achieve a .500in high front blade it may be necessary to first install a front ramp base .225in high (from Marble's I think), and then add a William's or Marble's dovetail front blade (fiber optic, white or brass bead) as close to .275in high, as possible or is available.
Similarly one can choose from an assortment of rear sights (complete assemblies or various parts to create your own).
Personally with aging eye sight I like red fiber-optic front blades that are 3/32in diameter - versus 1/16th inches diameter. Also for rear peep-apertures I really like brass-highlighted "twilight" apertures.
If you decide to try to wade through the many MANY choices available for front and rear sight-possiblilities, one could spend considerable time looking at ALL of them! So go equipped with a little bit of time (or lots of time) and some patience!
I can tell you that both Brownell's and MidwayUSA are good about taking back "returns" if one finds himself with parts he doesn't want to use and hasn't opened.
