I found this jacket with the Holley carburetors patch, and had a seamstress add the vintage Mercury racing patch I picked up from an online auction.
One of my good car-nut friends is a graphic designer who has done a lot of excellent automotive graphics work, including some for the Delmarva Cougar Club, which focuses on 1967-73 Mercury Cougars. He's done some great T-shirts and decals for us, and when the club celebrated its 10-year anniversary, he designed a huge embroidered patch that we had made for club members. The perfect way to wear the patch is, of course, on a vintage racing jacket. Our club colors are yellow, red, and black, so this jacket was perfect for the patch.
I've found these racing jackets in the usual places, online auctions and vintage clothing stores, thrift shops and the like. I've scored a couple from the online store The Rusty Zipper. If you haven't visited there, check it out, they've got a ton of nice vintage clothing with good photos and size information.