Been awhile since I checked in here. No offense intended, but a lot of misinformation here.
Ah - the interdynamics company in the link - the company responsible for bringing you "arctic freeze", or "black death in a bottle", containing sealers that spell certain death for your A/C system. I would never TOUCH their "complete" retrofit kit if you ever want a functioning a/c system. Their retrofit adapters are probably OK, and I see they sell the retrofit labels, so at least they're doing something right.
First, when retrofitting to R134a, you need to be aware that R134a is not compatible with the mineral oil used in the R12 system. Thus, the correct way to do a retrofit is to remove the lines and flush them of the old oil. You should also remove the evaporator and condenser and flush it. When adding back oil, be aware that the BVA Auto 100 oil is compatible with both R12 and R134a, so not a bad choice. As for the compressor, it may be that the seals are not compatible with R134a.
Then, while you have the system apart, you'll need to replace the receiver/drier while it's open as standard procedure. Additionally, the cooling of R134a will not be as good as the R12 was with the stock setup, so I would HIGHLY recommend converting to a "parallel flow condenser" which is just a fancy name for a condenser that has a lot more surface area to transfer the heat. The A/C system on these accords were fairly marginal to begin with, so going to R134a without updating the condenser is asking for pretty substandard cooling. This will most likely mean custom hoses for the condenser.
The service center is probably quoting you a pretty reasonable price for a job done properly. The car may not be worth it, but the more important question is, is your comfort worth it?
Personally, I have a 92 accord with R12, and I'm sticking with R12 only in it. Even with that, on those 110°F days we have here in Arizona, the A/C system barely cools adequately in the front. We got a van with rear A/C primarily because the (stock) A/C is not adequate for the kids in the back. I'm planning to change the condenser in the future, but keeping with the R12. Yeah, it's expensive, but I bit the bullet awhile back and got a tank of the stuff since 2 of my vehicles are R12, and I plan to keep them that way.
Chad
BTW, if you want to do the job properly, check out
this forum. I'm not affiliated with them in any way - just know that you'll find a lot of good info on servicing your a/c system over there. Do a search for "accord" and a number of retrofit topics come up.