re: Is this normal for a gunsmith? (Hope that's descriptive enough.)

Not all gunsmiths will do trigger jobs especially on specific guns.
When calling around, you definitely want to ask them if they specifically work on certain guns especially on the trigger.
Most will do basic gunsmithing like sight replacement, replacing springs etc but some items take more skill.
Not sure about 1911s but certified armorers in specific brands will usually do most intermediate to advanced gun work.