The reality is though, if a gunsmith does not charge rates commensurate with the actual cost of a job they will not be gunsmithing for long.
I looked at what it took to pillar and bed a rifle in my own workshop: Measure up and turn the aluminium pillars to size and drill centre holes (1/2 hr), Remove old bedding material or wood from stock below barrel etc (1/2hr), set up drill press to correct depth and forster bit the main pillar hole and rear hole (1/2hr), introduce action to stock and pillars and make any minor adjustments (1/2hr), tape and dam the stock and action, check that all fit with the action, adjust where needed, coat action with release agent, mix bedding compound and assemble the components (1hr), break out action and trim and adjust where needed (1/2hr). That's 3.5 hours and I usually took longer to ensure a really good job. So lets say 4hrs labour plus materials. I don't know what a gunsmith in the UK charges per hour but I used to charge $40/hr (10 yrs ago).
So I'd say that if the GSs in the UK are charging 20 quid an hour then 100 quid for a pillar and bedding job is realistic.
I didn't include the checks done with a bore sighter to check for springing in the action when tightening the stock screws as that is me making sure it doesn't come back with a 'strung' target.
My first post didn't take into account the exchange rate between Stirling and Dollars Au.