Deck post plate shim

I am looking to shim up my post plate on a concrete pier 1/4” - 3/4”.

Is azek acceptable to use? I can’t find any galvanized plates that are 3 1/2” or 6”.
Is there any other place that I could get plastic plates?
I don’t want to shim on top of the base since I want the nails to have the proper installation height.
I want to have full contact from base plate to pier.

 

Depends on what is being supported above…
What is the application and what Simpson post base are you using…

 

Offered in 3.5x3.5 as well...

https://www.lowes.com/pd/Simpson-Strong-Tie-6-in-x-6-in-Wood-to-Concrete-Retrofit-Base/1002709750

 

Azek (PVC) isn't structural. Simpson Strong-Tie makes a composite stand-off. CPS10 is one for a larger post.

Google that and I'm sure you'll find something useable.

 

Or exactly what opinion914's post linked you directly to in the post above mine.... lol

 

I found I can use HDPE under the bases. The compression is far superior to wood and can be obtained in sheets of various thickness for cheap