Not too tough of a project Dunkler. For an easy to run set, get a small bellow 'kit' from THO Al in his store. Comes with a 1/2" bushing for your reed. So, drill a 1/2" hole in your blank, and get it turned.
You will find there is a lip on the bellow. You will want to make cuts to your wood blank for this to fit. It will not stay on the call for any length of time without some glue. I'd recommend using Plumber's GOOP for attaching the bellow to the barrel.
The tone board is stainless over mylar. Put a razor blade under them, and blade them up to where the stainless stays sticking up, and you put a crease in the mylar. I call this "blading the pizz out of it". It is a LOT of blading compared to what you would do for a call for predator hunting.
I'd personally get 2 or 3 kits in case you blade one too far, or can't quite find the sweet spot in one when you work with the bellow. I personally ruin probably one out of every 10 tone boards. Ruined is a harsh term though, because they will still work at low pitched blow-through predator call guts.
Use the case of a Bic pen to push the toneboard and bushing into place.
Point the guts in the call away from the bellow, so when the bellow fills, it pulls air across the toneboard. You can put them in the other way too, but make sure the toneboard is completely inside the call, or you run a BIIIIG risk of someone popping on the bellow hard and ruining the reed. Sucking air across the toneboard, like I first said, has given me the most authentic sounds.
Total barrel length.......look at something between 2 3/4" and 3" for the whole thing, including the area to attach the bellow if I remember correctly.
No doubt you can also make a call without a bellow, using the same gut, to where you would just blow across the call in the correct cadence. It would last longer getting beat around duck hunting, and can also double has a teal call.....again..... with the correct cadence mastered.