Look online at Caprine Supply.
If you are milking up to 6 does, it would probably be cheaper to milk by hand. We did not switch to a machine until we were milking 10-18 daily.
You don't need to change inflations between each doe. Instead, you should have a bucket of sanitizer and drop the inflations in it as you change does off the stanchion. After removing the inflations you still have to strip the udder by hand. The important thing in dairy sanitation is to wash the udders before and after with a good sanitizer (we used (Iodophohr) and then seal the teats with a teat dip after milking. After milking, run the sanitizer solution from the bucket through the inflations and machine. Then remove the lines ad inflations and bring them to the house where they need to be completely disassembled, washed in cold water and a special dairy soap designed to cut the milk solids. Then they need to be dried (I air dried them) and reassembed in the evening for the next milking.
First time dairy goat owners think a milking machine will be easier than hand milking, but it is not. Hand milking gives you the chance to check udder health. Washing the udder before miking allows you to gently massage it which will let down the milk easier. You will find any lumps or sores and can treat them. Also, if you do machine milk remember to squirt a small sample out of each teat before attaching the inflations to check for any change in milk consistency which could signal mastitis.
We started with a small machine and eventually graduated to a larger machine. The small machine went to the shows with us while the larger, bulkier machine remained home. We had 2 double stanchions set up, side by side.DS2 would put 2 in at a time and while they were being milked, he would switch out 2 others. He could milk 12-18 in under an hour, including the set up and take down. Of course, he had learned to hand milk at the age of 6, and our dairy herd were all trained to come to the stanchion when called.
If you decide to buy a miking machine, try to buy locally so repairs and parts will be available. Read all the comment on the various kinds before you buy. Our first machine was very fragile.