Customs brokerage for US to Canada LTL?

I work for a book publisher and a new customer of ours wants us to ship a pallet directly to him in Canada. I'm new to this world and am just learning about customs brokerages. We have carriers we can use to ship, but they don't provide customs brokerage services. Since a lot of customs brokerages can also do the shipping themselves, it seems silly not to get quotes from a few for doing the whole deal. There's thousands of customs brokerages out there, and one of the carriers we partner with sent us a list of about ten recommended brokerages, but that seems like overkill. Anyone have tips for finding the right one?