Not that I can calculate an "authentic" price, but years
of browsing online says the price is competitive.
As to any loss of value due to a refin, a good refin, it's
not really an issue. While there is a following for early
MM basses, it's not an absurdly inflated COLLECTOR
situation where originality is at a premium. So even if
there is some rule of the marketplace that says a refin
drops the value, it drops so minimally that everything
else about the bass is far more important. $2500 or
so usually buys an early StingRay with natural finish,
sometimes a bit less $$ depending on condition. Over
$2500 is seldom seen.
What if someone had put in a non-MM pre-amp years
ago and a more recent owner has replaced that with a
proper-for-the-era MM pre ? No harm, no foul with MM
basses. But if it were in a collectible Fender, the visibly
non-vintage new solder joint, and a marking on the pre
showing it to be a year older or newer than the bass,
would be the difference between a $10,000 bass and a
a $5,000 bass [or worse]. Thaz the Fender thing.
With early MM basses, 100% perfect originality is pretty
much a side bar, a curiosity, and is worth a sort of token
difference. With MM, if it IS what it IS ... has all its right
elements and is in nice shape, nobody cares too much
about a refin or "wrong" date on a pot or a neck. No one
cared about any of that crap back when those collectible
Fenders were new, or were just "used basses", either. In
the MM world, Collector Insanity holds verrrry little sway
concerning price.
MM peeps are players, not curators

There's less than
several historically significant individual MMs out there.
Those are what they are. ALL the rest are for us players.
So, buy the damnt thing if it has no functional troubles !