So I've had my 14g industrial for about 5 months now and would like to change it to something else and I got curious about what kind of jewelry I could possibly use with this piercing. Like can I use labrets, tragus, helix or plain stud with rounded backs or the same gauge? I've tried looking it up, but I can't seem to find anything.
Tragus and helix are types of piercings, not jewelry. If something is marketed as a tragus stud, helix stud, etc. it's low quality and should be avoided. High quality body jewelry is very versatile, there are a few basic styles of jewelry that are essentially used for all piercings (straight barbell, curved barbell, circular barbell, labret, rings). You will more or less be limited to straight barbells for industrial piercings. Of course there are an endless number of different ends you can choose from. Keep in mind after only 5 months your industrial is likely still healing, they can take upwards of a year to fully heal. If healing is going well and you really want to have the jewelry changed I'd suggest having it done by a reputable professional piercer.
Two curved barbells could replace your industrial piercing, you should select barbell with length for you comfort and additional length.