I looked up pushers too.
And even though some are "universal", they're for pistols.
But I also wondered if one of them could be used for this application because the rifle barrel itself is smaller than a pistol slide.
But the magazine tube would also be in the way.
Even if it were removed, I don't know if these pushers would work as advertised on this particular sight, and may even cause damage.
If you don't feel comfortable doing it, then try to find a competent friend [or gunsmith] who would be willing to help make the adjustments for you.
It would be helpful to determine the amount that the sight actually needs to be moved to help minimize errors.
There's a formula that can used.
I looked it up:
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The formula for front sight adjustment or replacement is:
Record:
error on target in inches
distance to target in inches
sight radius in inches.
divide error on target by distance to target,
multiply by sight radius.
The sight radius is the distance between the front and rear sight expressed in inches.
If the rear sight is adjustable, adjust it to the middle of its adjustment limits to allow a range of adjustment up or down after replacing or modifying the front sight.
For example, if the sight radius on a pistol is 10 inches:
error on target= 12" low.
distance to target is 900".
sight radius is 10".
12" divided by 900" = 0.01333 x 10" = 0.133".
The front sight has to be lowered by 0.133 inches or a bit more than 1/8 of an inch (.125).