You can have a new muffler and/or tail pipe welded on. New aftermarket assemblies are available as well. Just take it to an exhaust shop and get a quote. Expect to pay between $100 - $150 (if you're in the US) depending on how extensive the rust damage is.
"General Tech" is exactly the right place for this question.
You can't solder exhaust, but if you can weld then that's the preferred repair. Else you can replace parts of it with cheap universal exhaust parts and clamps allow you to install without welding. If done right it's an acceptable repair but probably only lasts a couple years.
So, the rear of the muffler, where it comes out and into the tail pipe (or directly into an exhaust tip) is rotten. Is the rot in the attached pipe, or in the muffler's own outlet?
For reference, here's a picture showing the muffler's outlet. If that part is rotted out, you will probably need to replace the muffler before it will pass any kind of inspection.
There's a slight possibility that you could get away with exhaust "bandage" type products.
Luckily, universal mufflers and exhaust pipes are very cheap.
On a car I was only planning to have for a short time I got away with clamping on a universal muffler where the original broke off from rust. I was in a tight spot and it only cost about $20 to fix with all new hardware and an hour or so of work.
The best thing would be to get a section welded in where yours is rusted out. Most often, when a part of an exhaust is rusted off, most of the rest of it will follow. Either due to the overall condition of the exhaust pipe being rusted and deteriorated or the welds being that way. Often in low quality parts the welds won't be of the same quality as the exhaust and they will rust out before the pipe. Probably what happened, which also means it usually all fails at once.
Good luck with the truck! Rangers are generally good little trucks if cared for somewhat well.
On the never-ending quest for better gas mileage...
I work at a shop that does exhaust so here's my $.02
just take it to a shop and ask. it's free for them to look at it and tell you how much it will be. you can ask us all day long and put up pics but it means nothing because not one of us will actually be repairing it. you're wasting your time and our time to ask here.
there are two possible outcomes: they can weld it and it'll cost $20 or they have to replace parts and it'll cost $100-200.
1991 Toyota Pickup 22R-E 2.4 I4/5 speed
1990 Toyota Cressida 7M-GE 3.0 I6/5-speed manual
mechanic, carpenter, stagehand, rigger, and know-it-all smartass
"You don't get to judge me for how I fix what you break"