Inflatable new transom

[ithet]

I have an Bonbard AX3 mini rib whose transom has rotted badly. The professionals tell me that they do not do these repairs anymore, and would probably not be cost effective anyway. There are many youTube videos showing how to remove old transom (heat gun) and glue in a new one, and I will give it a go. So to my question, I have a piece of board that I assume is ply, from an old 1950's plan chest. Is it likely to be suitable? I realise that depends on the glues used, so wondered what those familiar with such material might think? Could it be useful if epoxy coated? I don't even know if my Lidl jig saw will cut it anyway.

 

[penfold]

Don't even think of using anything that's not marine ply from a reputable vendor; it will delaminate and render your efforts a waste.

 

[B27]

If I had confidence in my ability to do the fabric work, and I thought the fabric would last a decent time, I would want to use something a whole lot lighter than the original great lump of ply.
Maybe FRP foam sandwich, just reinforced with ply where the engine goes.