It "may" be something like this.
If you look on the acrylic lens, you'll find the model number very, very, very lightly imprinted. Use that to search for the gasket. If not, search Bomar's site and their manuals will help you identify your hatch.
Second question - also seems to be leaking around the "dogs".
As far as the leaking dogs go, I'd guess that the drunk you acquired from the gin mill and then paid to do the repairs, forgot to replace the "O" ring in each dog :
If you're smart, you'll do the job yourself after reading the Bowmar manual. This is TRULY one job which requires a Grade 4 Reform School education at best. Could have saved the the gin money as well. Bomar has a good selection of manuals.
When you put the dogs back together, lubricate the "O" ring with a NON petroleum based grease. Use a petroleum based grease and they'll leak in time.
Also, give the gaskets a wipe of this :
......... every other year and they'll outlast the boat.