A/C Compressor on '98 Sienna

[jctc]

I have a 1998 Sienna XLE with a seized A/C compressor.
It was diagnosed by a trusted independent technician and given a big price for repairs. Something like $2000-$3000.

This includes replacing all the lines in the rear A/C system, evaporator, etc. They said that there is no filter for the refrigerant and so metal fragments could ruin any new parts installed. The high cost comes from all the labor it takes to replace the rear system.

I balked at the high price and they came back with some options. I could get a used compressor, I could skip the rear system and hope that no metal ruins the replacement compressor.

My question is: can I just seal off the rear A/C system? I have no idea if this is possible, advisable, or just crazy.

Thanks in advance...