I just use common old grease with no problem on Lewmar ST's. Just look for the grease from your favourite oil
company with comments about "superior resistance to water
washout", "high performance lithium
based", "severe operating conditions", "extended relubrication periods", etc. You will find the stuff easily enough because all of the common old automotive, etc greases these days will do all of that.
I have been using a tub of the common old Mobil XHP version for years, the current
product name here (they tend to use different product names in different countries so may be different to where you are) is Mobil XHP222.
Mine is a pretty blue colour which I am sure is important, probably because it means that it is not priced as if it were gold
A friend who is a boatbuilder
told me many years ago he used such greases for everything, after looking at me as if I was daft when I asked about the need to use the winch
manufacturer's own greases or anything special.
In case not known only oil the pawls and their springs (as another has already warned) and on the Lewmar web site you can find full maintenance
instructions plus complete exploded parts
drawings for all of their winches.