Leveling Inside of Sump Basin

Replacing sump pump (dewater, not sewer) and I have a 18"dia x 22" deep "plastic" basin.
When it ws install they tilted it such that the base is not level. Its not bowed or anything, just not level.
So when pump sits in basin the 1 1/2" PVC discharge is not vertical. Old install had glued PVC and with elbows accounted for non-vertical line.

Before replacing pump I would like either:
(a) Suggestions on leveling pit or
(b) Ways to level pump. Its a Liberty 257 and was thing of seeing if short sections of PVC could be used as adjustable feet...

Any help appreciated....

 

In many installations the pump is not set at the bottom of the pit, but up on a block or blocks. If it's that bad you could simply pour 2 inches of concrete in the bottom of it. Another alternative would be to dump a couple gallons of pea gravel in it and then level a setting block on top of the pea gravel.