So, it looks like your primary problem is the aluminum ob the boom is failing.? Generally speaking, aluminum fabrication is less expensive in my experience. It may be easier to pull the end out of the boom and take the whole assembly to a aluminum fab shop.??
Do you have? any tuna tower builders or boat builders in your area. The boat builders might know who the good fab shops are. The work looks pretty straight forward. So you could probably mail it if you can't find local support.?
Rig right is a wealth of knowledge and parts but very hard to have a conversation with in recent years.?
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Carl Damm
DAMSELv
1976 #593
Stuart Fl