Broken Stemhead/bow roller assembly

I have seen the equivalent replacement fitting made up in stainless steel on a couple of club boats of similar vintage. So it can be done and you just need to find the fabricator who can do it. I would go for a double bow roller if it were me allowing more mooring and anchoring options.
 
Update on this - found a few fabricators who can do this in SS but they require the full part so they can work from that in replicating it. This would mean leaving the boat without the assembly for a period of time, without fairleads. As the boat is on a mooring buoy, any recommendations on how to keep the lines in place (cleats are OK) without them rubbing or chafing on the bow?
 
You could reuse the bolt holes and put a eye bolt through them and a lashing between them. your mooring ropes could then go under these lashings to keep them on the bow. You might get away with just lashing the mooring lines to the forestay fitting. In any case I would want to put a fair amount of padding ( like the blue plastic lower on your mooring strops) around the ropes as they go over the unprotected bow. All depends on how protected your mooring is and what weather is expected!
 
Welding an Al casting is a sketchy prospect, the metallurgy is generally not good for welding and it will always look like it's been bodged back together; the shape could be readily fabricated with stainless steel plate, although some stainless plate cut to shape and drilled and tapped or bolted to the broken parts of the casting could effect a quick temporary repair while a fabrication is made.
 
Could you put the boat on the mooring backwards. while the casting is away.
Maybe rigging it up with a rope to both sides.

You could use the boat as is for now but using an anchor would be hard work.
 
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