Eddie, from what I've seen, the coatings are MoS2- or PTFE-based, which is also the case for many oil additives. There are also ceramic and metal-based coatings, but obviously not DIY material (and probably not even available for short series or unit work).
And those are not dry-lubricant films, but rather hardening processes to limit scuffing.
I would not worry about lubricant coatings peeling off and plugging any oil galleys, as the skirt coating thickness is typically in the 10 to 20 µm range.
What would bother me in spray-base application (the only DIY method I would say) is how to bake the coatings without using the kitchen oven (your better half might be pissed if she finds out why the turkey smells like over-cooked bearing grease).
If you have a spare oven that can heat to 400°F, you can do it at home:
http://www.sandstromproducts.com/pdfs/e720.pdf
The info on this site :
http://www.jepistons.com/pistoncoatings.asp suggests that the hard coating type (TS) needs to be taken into account for piston diameter. Could there be problems if your uncoated pistons are already a tight fit into the cylinder bores?