I will be honest, your age doesn't mean that you are able to skirt the unwritten rules of turn out.
If you want to be taken seriously by a judge then you need to do what you can to look your best. If you can not afford a higher end show halter, than a plain leather halter would be better. Most important is the fit of the halter.
Not to pick on Duren, but that horse's head would look much better with wider cheek pieces and nose band. Also, it's too low on the horse's face. The rings by the nose need to fit in right in front of the horse's cheek. The rings below the buckle need to be right behind the top of the cheek to define the head and shape the throatlatch. The buckles also need to be tightened, they hang too low.
Now compare to this halter, by Deb Moyer (which is out of your price range, but should give you an idea of the fit to look for) Hobby Horse has similar halter that is tooled for less money, but I honestly am not familiar with the quality of HH tack: http://www.showtack.com/sb1.jpg