I want to make 2 of these in kevlar (the ends)
Any suggestions wat to use? I was thinking of a thin layer glass, carbon/kevlar and another 3 layers of glass. Will this be thick enough to have a smooth edge? I don’t want to have to razors at the end of my wing.
Usually something like this would have a core to add thickness without the part becoming vary heavy or expensive.
Any suggestions on the core material? Preferable household items 
You could use a wood core with two or three ply’s either side of it. Paint the edges of the wood black and most people wouldnt be able to tell that there is wood in the middle.
Wood core would be perfect, either birch or balsa. Birch core is probably stronger. Don’t worry thinking the wood will add weight, it won’t add but a few ounces of weight.
Try this lay up if you have some carbon fiber cloth:
colored kevlar/carbon fiber/ core/ carbon fiber/colored kevlar.
I mentioned colored kevlar because your wink mirror is hybrid colored cloth. Just assuming this is what you would be using.
The edges of the core that show when cut you can lay down some resin coats on the edges and tint the resin black or whatever color using resin dye.
We have a bunch of these to make for a customer in the next couple weeks. I’m going to lay up one large flat panel then cut the pieces out. It will take some time epoxing the edges and sanding them smooth.
Use a router to cut the end plates. That way you will have nice straight edges that will need minimal finishing amd if you clamp a bar or some box section as a guide for the router they will be perfectly straight.
A router will cut that amount of carbon easilly and wont really blunt the bit.
Adding to what Matvd said regarding the router. You can make a template the exact shape you want, use double sided tape to afix it to the oversize piece, and use a flush trim router bit to cut the wing end. All your pieces will be exactly the same.
Jon