Anyone know where I can buy an internal overflow kit?

[Aquatic Addictions]

We can make what suits you here locally. We can also drill tanks

[mark]

Try your DIY skills.

One bulkhead (2 if Herbie), 1 piece of glass for diaginal in the corner, 2 for a square/rectangle box, 3 pieces in the middle, some silicone and some masking tape. The lip does not need to be notched.