[Techman]

I've got this same model and I have to confess that I hadn't noticed that the transformer had a thermal fuse fitted until it was mentioned here and I looked again at the circuit. As far as I know this model isn't known for cooking its mains transformer, so the fact that it has gives a strong indication that something else has gone seriously wrong in the set to cause it to go. So perhaps I'm stating the obvious by suggesting that the fault within the set that caused it to blow in the first place ought to be found before even thinking about fitting a replacement transformer.

Having found the fault that caused the overheating, I'd then be looking to repair that thermal fuse. Transformers like this tend not to just go open circuit, but rather get very hot and fizzle with some smoke and dripping tar or wax, which I'm guessing yours hasn't done, having been protected by that thermal fuse device, so I'd be looking at trying to fix that first.

Unless the set is a mint example, or has special sentimental value, then I wouldn't waste a lot of money on it. There's plenty more out there to be had for not very much!