I cast one for my EQ6 in Aluminium
I did have a forge but you can make one easy with a few bricks or clay, and used a leaf blower, charcoal from Bunnings. and fashioned the mould in clay from the side of the road with a bit of sand ( you can find how to make moulds and the sand on the net)...used a big sause pan to melt the aluminium in..and had to file the casting down a bit to finish it neatly but it was a lot of fun and most satisfying to pull it off. You cast it with any holes needed but you could drill later of course but I just wanted a challenge.
I did make a pier and all out of ply wood covered heavily in fibre glass and resin with black tile grout, for my EQ 5 which turned out very strong and flex free so I expect you could make what you need in wood and layer it up in fibre glass even.
Alex