I tried but cannot get the 5052 H32 in the .025 thickness locally. I can however get it in .032 thickness in a 4'X12' sheet for $57.00. Sounds pretty reasonable. I've seen that the .025 is recommended. Would it be unadvisable to use the .032???
You will have a hard time with the thicker material, and the added weight doesn't help any. I say continue your search. There must be an aircraft place somewhere around redding. Look for an aircraft repair business or truck trailer repair place if nothing else works.
Rich the Viking