1999 Honda CRV Help assessing price quote

I took my 1999 Honda CR-V to my local repair shop that I have dealt with before. I could hear a tremendous squeaking over bumps while driving, coming from the rear axle area, particularly on the left rear side. They called me and told me that the entire back end was rusted out; bushings, shocks springs, stabilizer arms, etc. I saw this for myself when they put it on the lift and showed me everything. According to this shop, they could not order the bushings without order then entire arms and together with all parts(shocks, stablilizers, etc.) And approximately 5-6 hrs of labor the cost would approach $2300. Does this seem appropriate? I would like the vehicle to last one more year, as the mileage is low and basically the car is in good shape.
The car was never in water, but apparently parking on a dirt surface has contributed to the amazing amount of rust on the underside. (I live in New England). Thanks for your thoughts.