3-Point Seatbelts for 67

[MWHurt]

Greetings all, I'm looking for advice on where to get the best value on some 3-point seatbelts for my 67 longbed stepside. I live near and work on a Marine Corps base, and I dont' want the constant hassle of explaining to the Front Gate that my truck wasn't equipped with them. I'm new to the thread, and currently forward deployed, but look forward to adding some pictures when I get back in the States. Thanks for any help.