Folding trailer tongue kit/hinge

I am looking for a kit or hardware to allow me to hinge the tongue on
my bass boat such that it fits in my barn a bit better. I've started to see
these on some newer trailers but there is nothing wrong with the existing
trailer. I did find a hinge for $210.00 at a local trailer place, but it
seemed
a bit pricey to me.

I've spent a couple of hours searching the net, but couldn't find anything.
I have considered working with a local machine shop or weld shop to
customize something for me, but surely, this is a more common problem.

I intend to cut the tongue and simply insert the hinge. I can even weld it,
however, the one I saw used to half inch bolts.

If anyone has a source, please respond via email as well as the group.

Thank
earl