Welcome to owning a late 80s XJ. I had the EGR replaced a couple of years ago. I think I paid about $10 less for the EGR and may of been the same for the gasket. I also had an hour of diagnostic which included installation. I think the dealer EGR came with that silver dollar sized vacuum valve and hoses, the parts store one did not. They only used that EGR on XJs till 90, in 91 the EGR went away. I paid $171 to the dealer do figure out my problem and install the new EGR.
On the engine and transmsision mounts remember they isolate vibrations from the passenger cabin. If this is your daily driver I'd recommend staying with the OEM mounts, if it is your trail rig then the MORE mounts may do the trick. There have been countless posts on guys installing urethane or the MORE mounts then going back to the dealer mounts cause of the vibrations in the cabin.
I checked and in 2000 paid $41 for a transmission mount, and $27 each for motor mounts (P/N 52019201). The trans mount seems in line but confirm the motor mount price, almost sounds like they priced you a pair. Also ask him the Part number used on the wrangler, think it may be the same. When I got my mounts the XJ was in production, now it no longer in production, that may explain why the price has gone up. I'll put in dealer mount next time my rig needs them, if if the cost is more than you quoted.
Also, there is a Tech bulliten out on motor mount bolt torques. You can get teh values if you have a subscription to
www.alldatadiy.com I recommend if you have a subscription if you plan to keep your XJ, worth the $25. The TSB on Alldata was the ONLY place I found these revised torques, my facotory book only had the published value, not the revised value. They changed the torque on the through bolt. Also the alldata instructions for chaning the engine mounts were very good. This one repair would pay for the subscription.
One more thing if you change the motor mounts you will have to pull off the oil filter mount, make sure to pick up the three O rings. They should run less than $10 for all three. The Part numbers for my 88 XJ should be the same for a 89, you need one of each PN:
* 33002970
* 33002971
* 33002972