Hi Rick,
You really seem to have built up an interesting collection of lock mechanisms!
Although I would have assinged your nice miquelet mechanism - please note the rarely preserved leather or lead ? fodder for the now missing flint still present in the jaws!!!

- to the mid or 2nd half of the 18th c., there are only two members of the Gómez dynasty recorded in the most quoted - though far from being infallible ! - record of gun and crossbow makers, re-edited by Eugčne Heer in 3 vols. by the Journal-Verlag Schwend Gmbh, Schwäbisch Hall, Germany, in 1978:
- Gómez, Juan, Sevilla, recorded in 1624
- Gómez, Juan, Eibar, recorded in 1802.
Honestly: would you wish me to decide, I would, based upon the as-new condition overall, with no scratches visible on the steel, as you pointed out, plead for a period of origin of ca. 1800.
The flint fodder denotes that a flint was present for a long time in the dog jaws. You may be right in surmising it was a demonstration copy for display in the gunsmith's shop to show his skill.
BTW, I would personally be highly interested in your earliest mechanisms: matchlolck and wheellock?!
Best,
Michael