Recommend box for 12 Orion H2 1200 watts

Got my Orion H2.2 12" sub wired @ 1 OHM and it bumps beautifully. Problem is, the box I had made isn't thick enough wood. It's only a temporary box, uncarpeted, and only 5/8" thick. The installer at the car audio shop (they did the sub, amp, and distribution block setup all for $140) said the sub would blow the box apart, and I can already see the front side slowly separating from the rest of the box. It's a nice box, dont get me wrong, but no way can it handle the sub in 2 months time. I ordered a vented box from Sub Zone that's specifically made for the Orion H2, but they emailed me and said sub zone discontinued it! So now, I dont know where to go. I liked the idea of having a box designed specifically for my sub, but I guess I have to go with a universal one. What is recommended? I want to buy one online, not make another. I would prefer it be vented, and less than 16" in height because my car is a 1996 Acura Integra, and even the 16" box I have now scrapes the top of the trunk and i would love something a little smaller in height and stuff.

Ah. Forgot, it needs to handle 1200 watts. The guy recommended 1" thick wood. I dont want to go over $150 overall with shipping

I doubt you will find one online that will hold up to that sub. You probably will have to make on (or have it made). You can look at Orion's website and get the dimensions for that sub.'85 Toy

I contacted Orion originally for the box stuff, and they gave me the exact same printout that came with my woofer itself, so I was like okay. Then I passed the job along to my dad who owns a cabinet shop (sweet), and he passed the job to some guy and the guy made it 5/8" in thickness and my sub is gonna blow it to pieces in months time. I haven't talked to the guy, it kind of went out of my hands and I'm just like thanks dad. I can't for the life of me find a box with 1" MDF wood online, let alone what I need.

Why don't you get the same guy to make it? Tell him it has to be 1" MDF and sealed with Liquid Nails and braced. Did he make the other one nice, just not thick enough MDF?'85 Toy