All professional paint products for Automotive or Industrial such as Dupont, PPG, Sherwin-Williams, SEM, etc. have had multiple 10-15% price increases starting in Q3 2021.
My company sells multiple brands through our Bumper-To-Bumper Autoparts stores and Car Color Centers... I have seen all the numbers. Many of the toners are on allocation and hard to come by. None of the vendors are really shipping well.
There is no special deal, particularly on high quality rattle can etching primer with or without Zinc. Really really recommend you stay with the brand that you intend to use for a topcoat. Paint finish and paint adhesion is a system and when you mix products, you are just asking for trouble.
"Rattle can" anything you are not going to topcoat with whatever you can find because it really doesn't need it at all but don't shave a couple dollars if you are going to do a nice paint job over it.
Nuff said ....