I need to replace the laser mast step receptacle at the bottom of the hull. I am not sure what it is called. Are they available pre made or do I need to make one? Anyone have any plans or knowledge where to purchase one?
Where is the mast tube that sits inside the "mast cup" you are talking about? The "mast cup" is basically just holding the mast tube from moving. So if you seat your mast tube in what you have left of the "mast cup" then all you need to do is add some fiberglass, epoxy, wood, cement, whatever you can find to ensure the mast tube doesn't move. The majority of people on here use thickened epoxy and fiberglass (strips or strand) to build up and reinforce the "mast cup" with the mast tube and the bottom of the boat. Should be some good pics or posts about it if you search 'laser mast step repair.'
To answer your question, nobody sells the wood piece you are talking about, you would most likely have to fabricate one yourself. Removing the piece in your picture might be a chore (I'm sure someone has done that) and you risk taking out the bottom of the boat with it.