Just spend the money and get it over with . . . the muffler shop seems to be quoting you a reasonable price. go ahead and do the additional thing for $25. Might be exhaust hangers or some kind of flange gaskets?
“thingamibob” isn’t very helpful . . . that could describe anything
Why risk a fixit ticket or some other fine for a loud exhaust . . . you’ll wish you’d gotten it fixed sooner, rather than later
$170 seems pretty reasonable.
Ah so its a fake dual exhaust-just splits off after the engine. Seems a reasonable cost but just be aware that after-market exhaust systems are thinner than OEM that you’d get at a dealer. I don’t understand his comments though on there still being half a system there. The issue is a LEAK, not noise.
Yeah, the pipes he put on are freaking thin and small and look stupid.
“So you could avoid spending more than 10 minutes in one spot parked, and you would be fine.” I haven’t been to SF for 30 years. Even that long ago it had terrible traffic jams. I would get it fixed now.
Unless I’m mistaken, no 1991 Accord was every offered with any kind of dual exhaust
As mentioned before, the EX model had a muffler with twin exhaust tips, but that’s it, otherwise no different than the cheaper versions
I thought OP said one of the exhaust tips is gone . . . still an exhaust leak, but all the way at the back, not all the way at the front
‘Just the tip’ huh. Dunno what you’re talking about mate. I lost an exhaust pipe, you know, one of those metal things that stick out the back of your car and shoot out some crap into the air. Have you never seen someone with an exhaust pipe that’s dragging? Mine looked a bit like that before it fell off. My other exhaust pipe seemed to be in fine condition. But I got the whole ‘muffler’ replaced because it was noisier with just one pipe, and looked worse too.
As mentioned before exhaust pipes go from the engine to the muffler, the pipes after the muffler are usually called tailpipes.
Because the tailpipes are angled down, the loss of a tailpipe can result in the exhaust getting trapped behind the bumper cover and entering the vehicle though the rear vents.
This is a picture of the muffler;
Ok maybe if you’re a mechanic or you know how a car works. For everyone else who sees a car as a mystery-combustion-rolly-chamber, an exhaust pipe is the thing that sticks out that you’re calling a tailpipe. 
thanks for clarifying though.