If it's not old, it's probably worth asking an engineer if they'd be prepare to just take a quick look at the picture.
I'd ask at a small repair shop, they will often take a look at the picture while you wait and advise you immediately. The big service centres will usually insist that you leave the TV and charge more the same info.
If it's poor regulation or there is excessive EHT, may be repairable but get an estimate. Forget it if it's a faulty tube.
Cobweb, January 2005