Hi Andree,
The Deep Trekker DTG2 products may fit what you are looking for. They are entirely portable with internal batteries, providing 6-8 hours of use with a 90 minute charge. Lightweight but proven in tough ocean environments. Here is the link to the specific page, https://www.deeptrekker.com/dtg2/
The DTG2 Worker package has a grabber arm and 100 meters of tether. https://www.deeptrekker.com/product/dtg2-worker/
Let me know if you have any other questions!
