Kayak, they will use a dose calibtator to set the dose at a specific level of activity for a specific time of injection. For different areas of the country, they would need to contract with local Nuclear Medicine pharmacys that handle Y-90 to supply their needs, like the one I work at. We receive Y-90 shippments a couple of times a week, depending on need for Sir-Spheres injections.
As far a local Vet clinics participating in RDGL, its not a big step at all. Many Vets do I-131 injections for cats. To handle Y-90 is bacically an add on to their Radioactive Material license. Nothing special for Y-90, since it is much more "user friendly" as compared to I-131.