Is there an inherent reason you want all the same size?
I know if you want to buy a box of 72, you may save money.
I pay a bit more and get my spokes here-
DT Swiss Spokes

You can buy them by the spoke.
I like this because I can use a different gauge spoke on either side of the rear.
On my hybrid 32 spoke wheel, I use 14-15 DB on the rear DS and 15-16 everywhere else.