Swing gate hinges/locks

Sorry if this is in the wrong place, first of all.

After shopping around pretty extensively for a rear bumper, I've decided to have a go fabricating my own. Going for a fairly standard design bumper, but I'm looking at doing a dual swing gate (one for spare, one for dual jerry cans) that either lock together or lock independently.

So I'm hoping some people here have experience with that and can point me in the right direction as to what hinges and locking mechanisms I should look at.