The driver's seatbelt in my '08 Dodge failed. I couldn't pull it out. Seems that it's controlled by a sensor under the seat and something in the belt retractor couldn't read the signal. Why would they make a seatbelt electrically controlled, anyway?
I couldn't find a used one so I had to go new for $300. It was a 30 minute job to install it myself, mostly removing molding to get at it.

Other brands have similar setups. They've deliberately done stuff like this to put us home mechanics out of business. Who the hell needs an electric seatbelt?

Your truck is probably equipped with a seat belt pretensioner. In an accident, it's a good thing to have.

Seat Belt Pretensioner

Nope, none on it. It's just that dealer parts are incredibly expensive. I needed a little plastic head for a WW washer on our car. It clips on the wiper blade. It's just plastic but they wanted $40 for one. I fixed it with electrical tape.
I read somewhere that if you built a complete car from dealer parts, you'd pay over 10x the cost of the car off the lot.

Some seat belts are under life time warranty can be difficult to get dealer to agree to it. Had a 88 Accura that Honda fixed 2 years ago, under warranty. You have to argue the safety aspect. And manufacture warranty. Google your research before you go in.

Ayup. Funny your should bring this up. We replaced one in the shop last week. A woman brought in a Mercedes GL450 with a broken passenger side belt. $799.00 (part) for the belt that her dog chewed through. Then she asked me how can she prevent her dog from doing it again. . I ever so tactfully said to put the dog in the back of the SUV behind one of those wire mesh panels. Not sure she got it.

Our dog did that in my wife's E430, I think parts and labor were ~$600.

Is there a dog food equivalent of mac and cheese?

Check Rock Auto.com for all vehicle parts Don't know if they carry the seat belts,but you can save a lot of money there

After I'd already bought and installed it, I found a place online that will repair them for a much lower price. Figures.

Interesting: I've been a strong advocate of belts for years. I had to drive my pickup for several days without one and I felt almost naked doing it. I've never been in an accident where a belt was needed but I had the feeling that I was in danger all the time.

The worst part was the dog was in the car for all of 10 minutes. We'd had some friends over for dinner and drove down the street to show them a property that was for sale as they were considering buying a lot to build a house. I'm not sure why we brought the dog, but we left her in the car while we walked around the lot with our friends, came back and one of the rear belts was nearly gnawed in half.

Funny thing is when we took to the car to the dealer one of the mechanics said he used to work for the Subi dealer and they'd get chewed up seat belts all the time.

Those belts are cheap. Buy one for a C172, I think they are about $4000.

Honda warranty seat belts for the life of the car.

But Honda doesn't make a 3/4 ton pickup.

Plastic OEM parts with mucho $$ price tags, IF they're even obtainable.

30 years ago I had a beater Plymouth Valiant, slant six. Plastic cam on the carb choke shaft (had the choke unloader hooked to it), disintegrated on the end the linkage attached.

"WE don't sell that part, but you can buy a rebuilt carb", said the MOPAR parts monkey. Um, no thanks. Drilled a hole in the cam where it was still cherry, made new linkage from a piece of "10 copper wire. Clunker had over 200K miles on it, when the next owner finally junked it (rusted out).

Years later, the nylon bushing on a 318 V8 distributor fell apart when I pulled the distributor (head removal for an overdue valve job).

Same deal: no part available, but we'll sell you a new distributor. Was gonna root for one in a bone yard, made a new bushing from a nylon plug that was in an A/C line set. Never any issues with it, years later.