Heavy duty aluminum manhole, alternatives?

[rkarakai21]

Just wondering if anybody has experience with these aluminum manhole covers. This is our aft engine access point. The original seal is shot which is it's own issue, and the handle on the lid has broken off prior to our ownership. I could clean this hatch up, maybe a bead blast or something, find the seal material, have a new handle welded on, but I'm curious if anybody else out there, probably on similar boats, smaller heavy displacement cruisers built in Taiwan has a hatch like this.

It has three turning dogs, with a shallow rectangular slot on top, the bottom of which is semi circular, in which fits a heavy steel T-Handle to lock them down. Problem is, these rectangular slots which were shallow to begin with have become somewhat rounded with age and use, and the opening device usually slips out when you are trying to dog down the hatch, usually causing more wear.

The t-bar that fits into the dogs has a rounded bottom piece about a half inch wide, that fits in the dog slot. Seems like a poor design from the start to use a shallow rounded bottom slot for heavy duty torqueing. But I digress.

My pictures show the relative size of the hatch ring, and I'm wondering if there are any more modern, heavy duty watertight alternatives that would work in this size, with a more positive locking mechanism. If this hatch leaks offshore, this is a potentially dangerous large source of water ingress for one thing, that could cause the bilge to fill up rapidly after taking a big greenie over the stern, furthermore, it leaks right ontop of our transmission and shaft coupling, which prior to our ownership it has turned from brand new to rusty in short order.

[rkarakai21]

https://drive.google.com/file/d/1FR6...ew?usp=sharing

https://drive.google.com/file/d/1aAm...ew?usp=sharing

https://drive.google.com/file/d/1jxW...ew?usp=sharing

https://drive.google.com/file/d/1jxW...ew?usp=sharing

https://drive.google.com/file/d/1bJq...ew?usp=sharing

[psk125]

These guys seem to be familiar with the type of hatch plate you seek, though the dimensions may not match.
https://shop.hamiltonmarine.com/depa...CHP%7CHCO.html
They're not cheap, but they would seem to work better than the one you have.