Man, the price of a decent gun belt is just nasty - heck, the price of just about any belt is stupidly high, and unless you are actually buying a quality gun belt, almost all leather belts now are nothing but glued together leather fibers, not real solid leather. And that kind of garbage is not worth owning.
But I have found two great options for heavy gun belts at great prices - these are THICK solid leather belts suitable for casual wear:
The first is a 1 3/4" solid Black or Brown Leather Holster Belt from Buffalo Arms for only $22.
http://www.buffaloarms.com/Leather_Holster_Belts_it-161754.aspx
This is a plain, unadorned single massive slab of leather - perhaps the best basic gun belt I have ever seen. The only drawback is that at 1 3/4" wide, it can be a bit too large for some IWB J-hooks (can't use it with my Alien Gear holsters).
The second option is an unbelievable steal, but you need to do a little work on it. Go to Harbor freight and buy one of their 2" Embossed Leather Tool Belts for just $8!
http://www.harborfreight.com/embossed-leather-tool-belt-47637.html
This belt is also a solid one piece slab of leather, not quite as thick as the one above, but still thicker than most other belts. It only comes in natural tan, so it looks a bit funny, and at a full 2" wide, it won't even fit many pants, but the fixes to both are quite simple. A little black die or even a simple coating of black liquid shoe polish makes it look like any other belt. If it fits your belt loops and your holster, then the 2" width really supports a gun of any weight without sagging. But I needed one just a tad smaller, so I just took another 1 5/8" belt and layed it in the back side to use as a straight edge with a pen to trace two lines that were exactly 1 5/8" apart, then I used a straight-cut Aviation Snips to cut down the lines. This gave me the perfect size gun belt AND a couple of 4 foot long rawhide strips for free. And if you do not already own a pair of metal shears or snips to cut the leather, just buy one at Harbor freight for $4 while you are there:
http://www.harborfreight.com/straight-cut-aviation-snips-39611.html
and you will still have a finished belt for just $12.
You cannot cut off the edges past the rivets that hold the buckle in place, so the head of the belt and the buckle are still 2" wide, but you can't really tell. And if you really want to finish it off nice, this belt is so long you have plenty of leather to just cut off the old buckle and replace it with one of the exact size you like. If you need a casual gun belt and want to save $50 to $100, you cannot go wrong with this option!