I have my doubts this is a job that can be done on site. The stone saws they use at the fabricator's shop are generally huge pieces of stationary equipment. This is not as simple as drilling holes for the faucet on site.

My guess is that either (a) you'll have to remove the whole counter piece or (b) you'll have to replace the counter material entirely. But no harm in asking a local provider to see what they say.

P.S. It's not just the stone that has to be changed. Most countertops have a plywood substrate, so that, too, will have to be re-cut to accommodate the new sink.

You will have a much better chance of finding someone to do the job and do it on site if you can live with a top mount sink.

We enlarge cutouts for undemount sinks on site with no dust or mess every day, then profile and polish the edges. It's not rocket surgery; you just need the right tools and knowledge. We have never removed a top to replace a sink the exception being Corian. It's a one-day job for one man, plumbing included. This is estone:

Notice how much more round the edge is than the pencil chip factory original please.

@Joseph Corlett, LLC, it's a 4' Caesarstone vanity with left offset sink. So no matching worries. The vanity is composed of two 24" base cabinets. This is a new installation and I should have chosen a larger sink, but I didn't so now I get to spend money or live with an irritant.

How small was the sink you had? You only have 24" so what size are you planning?