You can add a receiver peep easily by yourself, along with the higher front sight that gonna be needed to zero it (because the peep can't get as low as the barrel sight's line-of-sight).
Your BB94 should be factory D/T'd for the special side-mounted peep required for BigBores - the Williams FP-94-375, IIRC.
You can also add a tang peep, but may need a gunsmith to D/T one hole in the top tang for the sight base's forward anchor screw.
A tang sight can be zeroed with the issue height front sight, because it sits behind the receiver, ILO atop it.
Most peep users also remove the rear barrel sight, to clear the peep's sight picture, and fill the dovetail slot with a filler blank.
On some rifles, it may be advantageous to separately zero both a folding rear barrel sight
AND a tang peep, each for a different distance (open=short/tang=long), and fold the barrel sight, raising the tanger if/when a long distance shot is called for.
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