I don't think Klarius is same company as Bosal.
With catalytic converters on all petrol engines, the exhaust gets hotter more quickly, so even short runs leave less moisture inside. They therefore last a lot longer than they used to. (My Panda one was replaced earlier this year, at 11 years old.
As a result, the aftermarket is smaller and less profitable. Bosal pulled out of the UK a few years ago. I think Klarius may have taken over their factory, but were already an established European brand I think.
Speaking to my local garage at the last MOT, with the original exhaust condition an advisory, he said it was very difficult to get decent aftermarket exhausts, as they rarely fitted properly these days. He tends to go OE whenever possible as the extra cost is saved in the time making the cheaper ones fit. So, sadly, go with whatever you can get at an acceptable price, but be prepared for some swearing at it.
Or go Stainless. Just over £300 was mine, but I do intend to keep it for a while longer. Not viable for a cheap hack that'll be disposed of an a year or so.