Doug,
AHPC have a distributor in the USA- so you should be able to source parts from them.
"Fun in the sun" (see add on catsailor front page.)

As Matt said-if it has a lip on the transoms it's homebuilt, but if not, it still may be home built.
Not all home built boats have the lip. It's in the plans but does not mean the builder put it on the boat.
However your not allowed to build home built boats from glass so they are all timber.
OPen a hatch and look inside. If timber home built, if glass factory built.
There are other tell tail signs but looking inside the hatch is 100% and simple.

Regards,
Phill

I know that the voices in my head aint real,
but they have some pretty good ideas.
There is no such thing as a quick fix and I've never had free lunch!