10mm chain is readily available in galvanised chain. You can get G30, G40, G50 and G70. The higher numbers are stronger. G70 10mm is roughly as strong as G30-40 12mm.
Maggi are very respected chain makers and are Italian, where you are located. They sell G40, G50 and G70. Just beware that they generally make chain to order. Don't believe their promised delivery
In stainless steel
there are a couple of choices. 316L is reasonably readily available. If you search around, G50 and Duplex SS chain are also available. If you look at the German SVB website they sell Duplex SS. People love or hate SS chain. There are enough horror stories to make me wary. Crevice corrosion
is a problem. However, well made Duplex SS should be fine.
full time I can only get about 4 years out of galvanised chain even reversing it after 2 years, so SS has some appeal. Anchoring
part time in softer substrates a 12 year or greater life is common and I think galvanised chain is overwhelmingly the best choice. The exception is those boats that have a marginal chain drop from the windlass
. Here the slippery nature of SS does help reduce the size of pyramid and can mean the chain feeds without having to manually push it down. It also comes up a bit cleaner after anchoring in mud.
There are two types of metric 10 mm chain with different link sizes often called DIN and ISO. Most gypsies will only work with the correct type. Fortunately, unlike imperial chain, the link size does not change as you alter materials. So DIN 10mm G30 is the same link size as DIN 10mm G40, or G70. Likewise, DIN stainless steel 10mm chain is also the same link size. So you can change between different materials and strengths without problems as long as you don't switch between DIN and ISO.
Be careful, as it is easy to end up with the wrong sized 10mm chain. Check the link size of your current
chain and make sure what you buy is the same. Here is a good website with the different chain dimensions: