Main Bearing and Crank prices?

[J.McDonald Knives]

Was driving home and my CEL came on. Went to AutoZone to get the code pulled and got p325 (knock sensor). Since I have 210k miles I'm figuring I have main bearings going out. Need prices for least expensive main bearings, main seals, crank, and anything else I will need. OEM replacement preferred but if upgrade is cheaper thats even better. I'm pretty sure my knock sensor isn't going bad cause I pulled code p304 (CH4 misfire) at the same time which is probably caused by the knock. This is for an EJ25D on a 97 Legacy Outback. If you need a VIN number I can post it up. Also looking for OEM replacement injectors for the cheapest price. So far I found them for $55 each at Advanced Auto. If I find the crank and bearing upgrade for cheaper than OEM then if I need to upgrade the injectors I'll need a price for them as well. Going to order racing clutch kit and lightweight flywheel from boxer4racing unless I can find it cheaper somewhere else. Since I will be working on the engine I plan to upgrade the intake as well with CAI. If you need anymore info let me know. Thanks for the help.

[ouch1011]

Do you actually have an audible bearing knock? Because knock sensors have a very high failure rate on these engines.

Misfire could be caused by worn tune parts. Doesn't have to mean internal engine damage.

Either you are jumping to some pretty big conclusions or there is more to the story. Does the engine run OK?

[J.McDonald Knives]

Its occasionally misfiring and I'm hearing a slight bit more knock. I know I have run a quart low and not realized it but topped it off. I do run royal purple. I get close to 3k miles and start to burn oil. I know if I have to pull the motor to replace bearings I'm going to replace piston rings.