105 5700 is 10sp. If you are going to modernize and spend the money vs use parts sitting around), I would just do 11sp.

As for cranksets, use a shimano 105 crank or a shimano non-series crank like shimano rs460 or rs500 if you want a Shimano brand crank that isn't hollow(the potential design issue on older recent models). Or buy a praxis, fsa, Easton, Rene hearse, etc etc crank. Something made for 10sp or 11sp will work. The bottom bracket needed is just am English thread also called BSA.

I am unaware of a suntour 11sp crankset. Sugino makes multiple 11sp cranksets, but they are pricey and distribution was really limited even before covid so who knows on that front.
you could use an older sugino/sakaeSR crankset with modern rings if you can find 11sp ramped rings that fit the crankset spider, but maybe step back and ask if that is what would look and perform best before going down that kludge route.