Go to http:/www.hoyoa.com/eindex.html and click on products. You will see on the left a place to go to contact them. They made the charger however it may have been a limited run product for a certain company( Power Pro Craft CDD24D) and I don't think they store extras
The power unit that plugs into the wall is a 27.0 volt charger:
Model: BHY48-27.0V-400mA
Input: AC 120v 60Hz 20w
Output: 27.0VDC 400mA
Date code 200510
If they can't help there just has to be somebody out there making on similar to it so you might be able to jury rig something that will work. I happen to have one which I purchased at Tractor Supply(tractorsupply.com).
Good luck!