You can actually get quite cheap ones now. They make integrated scanners that work with a phone app. Easily under £1k second hand. Maybe close to that new if you shop around.
I wouldn't recommend it though. The only reason we use ultrasound imaging is because it's cheap, easy and completely harmless. As an actual imaging method it's terrible. There's so much speckle you can barely see anything, except in some situations like pregnancy where you have a convenient bag of water around the thing you're looking it.
There's a reason ultrasonographers are well paid - it's really really hard to read an ultrasound.
I wouldn't recommend it though. The only reason we use ultrasound imaging is because it's cheap, easy and completely harmless. As an actual imaging method it's terrible. There's so much speckle you can barely see anything, except in some situations like pregnancy where you have a convenient bag of water around the thing you're looking it.
There's a reason ultrasonographers are well paid - it's really really hard to read an ultrasound.