The Abilene show (at the fairgrounds) is this weekend, 4-5 December.
And, if you are not into that, Christmas at Fort Concho (San Angelo) is the same weekend. Usually, they have the crew from Fort Sill with the display of 1880's cannons (and sometimes their gatling gun) which they demonstrate as well as firing as part of the Retreat Ceremony performed by the Buffalo Soldiers. They will have reenactors from the fort as well as a variety of others on the parade ground.
Several of the barracks, the warehouse, and several of the officers quarters will have various vendors, as well as a suttler (usually) on the parade grounds as well. Sometimes they even have a blackpowder firearms vendor - usually Civil War era.