The plastic stackable/nestable containers are a good way to go since they are more durable and more easily sanitized than wood. A nearby source would be Nolts' Produce Supply, Leola,PA.. The 7/8, 1 1/4 bu. sizes are most used.
I don't have CSA but I always have trouble getting containers back from customers. I'd suggest a hefty deposit system to cover your costs.

Definitely put a deposit. I didn't have any trouble getting my crates back, but I only had 3 members, so easy to remember. I found some clearanced plastic boxes that I used.

You will most likely imprint your name yourself or finding someone else to do that AFTER you decide on the crate.

Marla

Nolts' is a great supplier and their prices are hard to beat.