I continue to research small form factor PC-based solutions.  There is a a company out of Europe called Digital-Logic with a MICROSPACE-PC family with a host of options with pricing starting at $1601 (discounts available for large orders), and go up to $4386 (bundled with 19" TFT monitor).

The distributor in the United States is Advanced Digital Logic based in San Diego, CA. [Which I have no affiliation.]