My thanks to you all for your inputs and suggestions on this. A set of Panaracer Paselas (27 x 1.125) are on their way to me for use on the subject rims.

Btw, running a lower pressure on the cheap 27 x 1.25 tires I previously tried on these rims isn't an option. Because of the combined weight of bike, rider and touring accessories I've found on my other road bikes that I have to run tire pressures near or at the max rated pressure.