Early Cat,
I would just check with any of the vendors on rebuilding yours or purchasing a new one.
I don't see one on PI Motorsports (pim.net)website but I would bet they could help you out. I also have used Dennis Quella in Castle Rock, CO for quite a few parts and would bet that he could assist you also.
I see that Hall Pantera sells a brake booster with master cylinder on their website for $425 with a $200 core charge. This does not look 100% original if that is what you are looking for though.
Click here for Hall Pantera's Brake Booster
Good luck.
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