Jim Davis wrote:

I have not enough aluminum tubing
for making tapered antenna elements :

OD ID (inches)
1/4 3/16
5/16 1/4
3/8 5/16

Where best to acquire more ?

Thanks ... Jim D

Small quantities of 6061-T6 from Wick's Aircraft 800 221 9425.
Perhaps Texas Towers also.

W4OP