Check Engine Light and Engine Misfires / O2 Sensor

Recently got a check engine light and went to my local auto zone to get the codes pulled. Need to pass inspection soon.

Looks like I have multiple problems, first with cylinder misfires and second an O2 sensor. My 2008 Prius has about 180K miles on. Replaced the spark plugs with OEMs at about 110K miles.

Codes are P0300/PO301/PO303 (Cylinder 1 and Cylinder 3 misfire detected)

Question is: Will replacing the spark plugs likely solve the problem or do I / should I replace the ignition coils as well? Coils have never been replaced. The Toyota coils are about $100 each at the dealer wholesale parts store. Can get aftermarket for $50 to $60 each. If I should replace the coils, is it worth it to spend the extra $ to buy the Toyota coils, which are about twice as much?

On the O2 sensor, code is P0137 - Oxygen Sensor Circuit Low Voltage (Bank 1 Sensor 2). I think I just need to replace the sensor as I don't think it's ever been replaced. Same question on Toyota vs aftermarket O2 sensor. Is it worth the extra $. I think this is the downstream sensor. My cat converter was stolen about a year ago. Replaced with after market and has worked fine since.

Grateful for any advice. My Gen 2 is 15 years old and running strong but thinking about trading it in. Hence questions on whether worth it to buy OEM parts versus aftermarket.

Thanks a ton.

 

Exactly what I needed. Thanks sincerely for taking the time for the response and advice. Going with OEM parts and moving out to see if that resets the codes. Many thanks!