I noticed that most of the chains i could find were relatively quite thin not really representing that of an actual boat chain.
This has just been a test to see if a heavier chain would print (and it does rather well.)
There are only 5 links on this but I have also put up the SolidWorks part and assembly files if you want to modify. If you want to add more links just add the part file in again and mate it the same way
I printed this with a Brim to hold to the table properly as the first time without this it came loose.
You may need to scale this down to the size you require.