High/low converters are generally built for car audio and home audio where the outputs are both low power and fairly standard across the industry. They will have a fixed attenuation and voltage range, but they probably won't tell you what either of those values are.
It might work, but I would not risk my receiver on one. A juke is designed to play VERY loudly compared to most home/auto audio sources. Especially with Ken's comment above, I would not expect it to work long term.
If you want to build a custom box to do it, you could look at the output voltage from the juke, figure out what voltage you want into your reciever, get a transformer with the correct ratio, then put a current limiter on it to protect your inputs, but I suspect that is far more effort than it is worth.