Any leather glove will work as a belay glove, but some are better than others. This Wells Lamont is one of our favorites because it is relatively durable, has a tight fit, is inexpensive, and is widely available. The $25 price is for a pack of three. As with all gloves, the most important thing is fit. The great thing about this and any leather glove is that your local hardware store will have something that works.
If you are just looking for hand protection, it is hard to beat these for the money. If you want a version of this glove that fits better, check out the Metolius Climbing Glove (five times as expensive). The Black Diamond Crag Glove is much better for dexterity when belaying, but they are also six times more expensive.
You might have a pair of leather gloves laying around that are suited for a conversion. If you do have to buy a pair, they are usually cheap and available at your local hardware store. I have found that as long as you get a tight fit, they have good dexterity. The Wells Lamont gloves have a soft and padded leather palm that is quite durable.
We found the first part to wear out on these gloves was the fingertips. No problem. We easily turned them into 3/4 length gloves by cutting the fingertips off (after first adding duct tape to keep the stitching from coming undone).
The issue with leather work gloves is fit and durability. A lot of models are too loose, especially around the wrist. It is possible to find leather gloves with a Velcro closure, but at that point, they get more expensive, and the main draw of the leather gloves is that they are cheap. If you are just belaying, a poor fit is not a big deal. But if you are rappelling and want some dexterity, it can be scary to handle these. Most leather gloves do not come with a carabiner clip in loop but this is easily solved by cutting a small slit near the wrist.
If you size these tight enough these gloves are perfect for belaying. For extensive rappelling, they will wear out much faster than a glove designed for rappelling. I bring them on big walls for hauling and dealing with rope issues in addition to my fingerless leather gloves for leading.
I just helped rig for the filming of Steve Wampler's El Capitan climb. There was a lot of heavy hauling and rappelling. While I brought fingerless gloves, I mostly just used these and the verdict… WOW!! Normally my fingertips turn black after a few days of using fingerless gloves. After two days on the wall, my hands still looked and felt great. I now have a brand new system for big walls: bring one pair of fingerless gloves for leading and maybe cleaning. Bring a pair of full fingered gloves for hauling, rappelling, belaying and everything else where you don't need tons of dexterity. Try it, your hands will love you!