You can get the mini anywhere, it's an OEM starter that began appearing on the trucks in 1994. They used to cost a lot more to replace or rebuild, so back in the day when they went bad, a lot of people replaced them with the more commonly available big starter. The mini is stronger and pulls less power from the battery, and these days they cost a lot less than they used to.
If you gotta get locally, it'll be from China but you can generally get them at any parts house for similar pricing. Not sure where in Houston you're at but I used to always get my starters and alternators from this place over on Aldine Mail Rt, called Wood Alternator. They're a rebuilder but they also carry new. I'm not on that side of town anymore so it's too far of a hike.
Richard