Here you go, from Gmail...
"What's the maximum attachment size?
With Gmail, you can send and receive messages up to 10 megabytes (MB) in size. However, the precise amount allowable will depend on the attachment.
When you add an attachment, the size of a file may increase because transport encodings are automatically added. (Transport encodings are the information that allows your message to be safely sent and read.)
This means that in some cases, attachments that are 6 to 10MB in size may push the total message size above 10MB. When this happens, Gmail displays a warning that your message exceeds the 10MB limit. "
So you cannot use the Gmail account to receive that size of attachment, even if you can get your server to send it.
Darrell gave you some suggestions has to how you can host this file and allow the client to collect it.
Dave
Dave