The exact OEM fit sensor is that price.  An equivalent universal sensor
is much less and does the same job for $45.

Of course your mechanic is like most in that they don't want to spend
time splicing electrical connections and they don't want the risk of the
splice not working well and having the car come back.

At the very least you could shop for the OEM sensors yourself and bring
them to a mechanic and say "I tried but I couldn't do it myself".  That
might save a couple hundred bucks there.

Dave

There are alot of "old school" mechanics out there that can't seem to
let go of the carbuerator or drum brakes. Computer based engines of
today can really throw them off, even though they mean well.

Your computer may have actually thrown all 3 codes, and the problem is
most probably just one. Logical deduction would have me replace the
most active ones first. That would be the 2 O2s shoved up in the
exhaust manifolds on both banks of your V6. Actually, replace the
front one 1st. You can do it yourself. After replacing it, see how the
car runs. Reset the engine light, and if you cant reset it, you may
have to wait a couple of days for the check engine light to go away.
This is no big deal and no major harm is coming to the car.

As a case in point about the check engine light, I had once let my
previously owned 94 Altima go way too long after it was supposed to
have its scheduled maintenance. During that time the car became
unstable, but I knew what was up. Then one day the car started
stumbling badly. Check engine light galore. I pulled 3 codes: fuel
injection system failing, O2s, catalytic converter, etc. Had I gone to
the dealer, they may have done the work and given me a whopping bill.

All it was was that I was long overdue for a tuneup. I changed the
plugs, wires, rotor and cap and all was good again.

Food for thought.

CD

A lot of people think that at this age/mileage all the o2 sensors
should be prophylactically replaced anyway.  Your mechanic might be
one of them.

P0130 is the pre-cat sensor on the right bank.  They are expensive if
you get the OEM sensor. If the other sensors are far enough out of
spec they will throw their own codes.  The ECM will store multiple
codes.  I would just test the one reported bad to make sure the
problem is not wiring (the '96 I routinely deal with is having a lot
of problems because the insulation on the wiring is hard and
crumbling), and just fix that.   If the other sensors are also bad,
they will throw their own codes soon enough.