Richardson Bikemart (at least the Frisco and Richardson locations) will happily work on vintage bikes. There is also Bicycle Exchange in Carrollton which specalizes in older gear along with some new stuff.
I too have had some trouble finding a recessed bolt for my Serotta though. I ended up buying one from Loosescrews.com, but got the wrong length. Next order I'll get the next size down and be good.
Good luck finding one local, if you do, let me know!