10 years is a good life span
to answer you question
it all depends on repair cost
weather you can afford to replace
The way i personally look at it is if the repair will cost more than 30-40% of a new tv then replace
so for example
a new standard 40 inch tv in the uk is around £200
so if the repair costs anywhere from £60-80 replace tv
or repair cost of £40 i would repair
but seen as this has happened to you once already i would suggest a replacement