On the assumption that you are looking for some company in Mexico to job the crosslinking process for you, I suggest you contact Radiation Dynamics Inc. (RDI) and tell them what you are looking for. Their web site is www.iba-worldwide.com/rdi/ . They are by far the largest supplier of E-beam equipment and thus should be able to help you.
There are companies in The US that provide this service. E-BEAM Services, Inc. has three facilities and is found at www.ebeamservices.com/ .