In the UK, look at BMI Baby...
I cant remember if theyve got rid of all their 300's but I'm sure there are still some around and even their 500 series 737's are getting old.
Some used to be ex BMI and I believe they had an ex BA one too.
Some are over 10 years old. Most of them 15 years or more.
I like BMIBaby but dont you think it is time they renewed some of their aircraft.