Frequently Asked Questions: There are very realistic sex robots, would purchasing one be ethical?
Purchasing one, as long as it is done in accordance with the laws governing such commerce in your area, would be perfectly ethical and even moral (those two do NOT mean the same thing, by the way).
USING one, on the other hand, is another question entirely.
Yes. As long as you’re following the laws as relating to your country, following the ethics of your faith (assuming you have one) and not violating any of your personal ethics, there would be no reason not to buy one of these.
A larger ethical question, I think would be if you or someone else is doing realistic 3D modeling of individuals without their consent.