There are a ton of regulations surrounding radioactive sources, homeland security, state regs, NRC, basically a huge pain in the tuckus, and they are thousands of pounds and usually require reinforced floors! I have used the linear accelerators in Radiation Oncology at a previous job and that worked really well, but we would occasionally run into "traffic jams" with patient treatment schedules. X-ray irradiators don't require all of the regulatory ridiculousness, but I have heard (but haven't actually used them) that if you are doing large volumes of irradiating, then you should probably have 2 because the x-ray tubes must be replaced after so many cycles and that can take a week or more. Also, many of the x-ray irradiators need to be plumbed with a water supply. Best Theratronics from Canada and JL Shepherd are the 2 companies that I know of for the standard irradiators. There is a really nice cost comparison paper from Wisconsin that you could read at https://www.lafollette.wisc.edu/images/publications/cba/2013-irradiators.pdf