Save your pennies and just buy the bullbar. For what they are and do they are worth every cent.
It takes usually takes 6-10 weeks for arb to design a typical bar, and that is using all the lastest equipment and technology available. There are more than 20 parts making up the average bar and they are all either laser cut profiles folded on cnc press brakes or cnc bent tubes, so unless your welder buddy has access to sheet metal cutting and bending machines, your going to have alot of work to do. And after welding they get shot blasted, phosphate washed and powdercoated. That is why they will last 20 years easily.
I can tell you that the arb bullbar wings, pan and coverstraps are 3mm thick, the uprights, winch cradle and impact absorbers are 4mm, and the tubes are 47.6mm dia with 2.6mm wall thickness.
If you do try to make your own, start by making a prototype out of cardboard (cheap, easy to get, easy to work with, doesnt matter if you stuff up). Then use your final cardboard parts to get your sheet metal profiles.