Don't be discouraged by the lack of tacticool gear. I have shot a grand sum of ONE 3-gun match in my life, and my vault is just as meager as yours, I assure you. My gear (magazines, mag pouches, hearing protection, etc.) for the match was almost entirely borrowed. My guns consisted of:
1) my EDC pistol;
2) a borrowed Ruger SR556 (loaned to me at the match by a guy after the Mini-14 that I took jammed); and
3) a 12-guage 870 with a Choate magazine extension.
I'll guarantee you that my entire setup cost less than some of the individual shotguns I saw. I was loading magazines at one point, and overheard one guy say, "Hmm. Looks like someone just brought out his duck gun." I interjected: "That would be me." His response: "Wish I'da thought of that before investing $3,000 in a new gun." I hadn't really paid attention to the guy, but to be fair to him I don't recall seeing his $3K shotgun jam. Then again, neither did my ol' duck gun.
I considered the 3-gun match to be, in part, training for emergencies. For that, you shoot what you've got, what you'll have in the event of said emergencies.
I'll go back and shoot another one soon, preferably after ammo prices come back down. I'll probably have to beg and borrow more loaner gear the next time, too. It's totally worth your time, though, and very educational.
I'm a lawyer, but I'm not your lawyer. If you need some honest-to-goodness legal advice, go buy some.