Here is one place you might find some. Unfortunately, there are several missing graphics. Those 2 are like checks, 3 up with a duplicate that stays in the book.
The other 2 are individual.
To be honest, this is my site. I sell loads of computer checks and invoices to POS customers I set up in the 90's. They still buy checks, etc. from me, so I keep up the site.
It is actually a wholesale side of NEBS. Same products and quality as NEBS, but usually priced lower.
I don't know if this is the answer, but you can get going for under $ 100.
Best to avoid the menu. Just type gift certificate in the search window and you'll go right to them.