Dirkwood,
There are a lot of Dexter breeders fairly close to you. You can find them listed with the American Dexter Cattle Association, the Purebred Dexter Cattle Association, and on the Legacy Dexter Cattle Registry. The Dexters are the same, only the politics are different.
I found myself in a situation similar to yours, where it was necessary to keep the physical effort to a minimum. I developed a lot of techniques for reducing labor. You might be interested in hearing of some of them. I keep diferent species that work well together to reduce my efforts. I also enlisted the aid of the USDA and Virginia agricultural experts to design my pasture layout for maximum benefit with minimum effort.
I run my 20 acres by myself, with a heart history similar to yours. If it weren't for the ease of keeping Dexters plus the symbiotic use of other animals, I couldn't do it.
Water is going to be most crucial to you, so make sure you have a good plan for it before jumping in.
Hay will probably be your second biggest need. It costs a lot more in Texas than it does elsewhere, so you have to locate a reliable source of reasonably priced hay. Note I said reliable and reasonably priced.
A lot of Dexters have changed hands in recent years because of those two factors.
You are at a good point to make a plan that will serve you well and make you a happy man in the future. Take time to start right and surely you will finish well.
Email me through the link on page two of my web site and I'll give you links to the USDA and State agencies that can give you a lot of guidance and assistance.
Genebo
Paradise Farm
http://paradisedexters.com