I haven't read much on internal brazing. I have a C. 1983 Peugeot P-4 Corbier, which I think for their later models fits me and rides better than the UO-8. (Then again we all have our preferences)

The bike was a base model.

It's HLE tubing, which is probably in the same grade as Motobecane's 2040, a slightly higher grade of Pipe-de-gas.

I suspect the bike may have been soft-crashed, as the fork is slightly off (bike tracks slightly to the right) but then again that could just be a bad fork bending at the factory. The bike doesn't have rippled paint or any other telltale signs. Generally, it rides quite well.

The frame joints look fine.

The "Internal brazing" looks impressive, I'm just wondering what's your experience.

Peugoet pretty much perfected good quality massed produced internally brazed frames in the 80's with their Carbolite and HLE tubed frames. I never heard of any of their internally brazed frames ever failing because of bad brazing. To top it off, although the frames were on the heavy side, they have some of the best ride of their time plus they are rugged and could take a lot of hard riding that an owner can throw at them so, if any frame could stand up to crashes well, I think Peugoet's internally brazed Carbolite and HLE frame would be one that could.
I suggest that you have your frame inspected by a good bike shop with the proper tools that can cold set it back to proper alignment.

Chombi

+ 1 to addressing whatever ails the fork. The bike is worth it.

Although the P4 Corbier is an entry level bike, it does not ride like one, (especially with alloy wheels and Paselas).

I too own a Corbier, along with plenty of '531 and Columbus and Chromoly bikes, but I still think HLE is pretty good stuff. HLE steel, or “Haute Limite Elastique”, translates to “high limit of elasticity”.

FYI, the 87 Peugeot catalog (https://cyclespeugeot.com/PDFs/1987pdf.pdf) states the following about HLE steel:

“HLE is Peugeot’s exclusive alloy tubing. It is a “micro alloyed steel” which is composed of Manganese, Nobelium, Aluminum, Carbon and Titanium, which offers a lighter, yet stronger frame. These4 elements are commonly used in the manufacture of aeronautical steel. The introduction of these elements results in a steel with dramatically improved mechanical properties when compared to conventional steel.

The strength to weight ratio of HLE steel is superior to that of conventional tubing. Using this tubing enables Peugeot to save more than 7 ounces in the weight of the frame. The HLE tubing, when used with our patented internal brazing system, gives Peugeot a frame which is at the top of its class in performance and reliability.”

I've got a Peugeot Touraine that's built from HLE. Gotta say, like all my other Peugeot rides, the quality of the ride is pretty wonderful. I've got a P8 made from Carbolite that is one of my favorite bikes.

I know, I saw that too, I thought that was pretty groovy. A wierd blend of mysterious elixirs. Nobelium? I love how the top tube is like 12 feet long on my 23" frame. It's really comfortable and it corners amazingly. I have double walled rigidas and Conti Supra Sports.

Do you consider the carbolite about the same as HLE? I always got confused on the two, I wondered if they had the two for sale at the same time or did one replace the other? There are tons of carbolites around here, but few HLE's.

I suspect "carbolite" is just a glorified name for hi-ten. Peugeot phased in HLE to replace and supercede carbolite. By the late 80s, I believe even their entry level road bikes were built with HLE.
I'm very pleased with my HLE constructed, internally brazed Versailles. It is my workhorse for daily commuting, when weather permits.

Carbolite/carbolite 103 is bascily hi-tensile steel. There is a 'lightweight' version of this metal. HLE tubing is significantly different.

Peugeots internal/external brazing is incredibly strong. Back in the day we had a customer who T-bones a car and bent the TT and DT in the typical places. The TT metal tore ~1/4" from the internal/external brazed joint.

I have a Canadian HLE Marseille that I ride a few days a year at my parents' house in Pennsylvania. It rides okay, and built up into a pretty light bike, but I find the dropouts to be a little less than refined. Also, the 23.8 mm seatpost would be tough to find if mine didn't come with the steel seatpin in it.

I just weighed my P4 (bathroom scale method)

It has Nitto alloy bars, new Weinmann Rm19 alloy wheels, the original steel chain rings, and 1x1-1/4 Pasela tour-guards on it.
- It tips the scale at 25lbs. (Not bad for an entry-level bike.)

Sweet. i'm probably pretty close to that, as I have decent alloys as well. I have pretty cool bars that I think were factory, they are steel but nice and wide and fairly light. The chainrings are decent also, I like their steel ones also.
I'm so glad to hear the internal brazing is so strong. At first I thought "this looks too good to be true".