Hmm. I really find it hard to believe nobody has these or can supply them to order. I had this sort of line fed to me a few times by garages in the lest few years for a variey of crappy eurpoean cars from Clios, Saxos, and a VW. They know the stuff is out there (on auction sites) but they (understandably) don't want to risk the liability of supplying/fitting, probably be fine if you did it yourself though... Anyway, there's nothing special whatsoever about most exhaust systems. I would just cobble one together from some pre bent pipes from demon tweeks
https://www.demon-tweeks.com/uk/performance/exhausts/exhaust-accessories/exhaust-pipe-bends/ or random tube bought from a metal factor to whatever the cheapest straight through silencer is in the appropriate flow range(it helps having a welder) or contact someone that knows what they're doing (eg maniflow)
https://maniflow.co.uk/ (they mainly do classic stuff but pretty sure they can make anything) or
https://www.merlinmotorsport.co.uk/s/exhausts. Depend on how much you want to pay really....
Rant ahead, potention TLDR:
That said being said.... I bought a (cheapish) and high mileage Octavia Mk2 VRS (diesel) estate 18 months back and it's really pretty awful, (much worse than the Passat or golf estates that I had previously) it weighs a hell of a lot, handles like a total dog (raised or lowered) and insists on destroying many rear tyres in very short distances (yes, tyre pressure good, tracking checked, suspension was lowered and has since been raised, camber checked, no signs of accident damage etc, yawn). Additionally 3 or 4 fairly expensive sensors failed around this time last year and the root was eventually traced to an EGR cooler which dumped £35 woth of coolant and antifreeze into the inlet manifolld at seemingly random intervals. Thenm there were related issues with broken wires in the loom between the crank sensor and the bulkhead. Basically it's behaved exactly how I'd have expected a Skoda to behave based on their 70s-90s reputation rather than the cheery reports after the VW takeover about them being a rebadged Golf or whatever. Looking at the forums rear tyre destruction, sensor failures, bad wiring looms and dead EGR coolers are worryingly common... terrible eastern bloc quality made from left over vw parts bin oddments. I hope the MK1 is better and I suspect it is if it's old enough to escape some of the hells of DPFs, EGRs, etc. Shame really as when my Mk2 will point in a straight line long enough it shifts quite well and cruises most economically in 6th gear but would I buy one again? Hmmmmm, not unless I'm in a hurry to get a car.
www.scorpion-exhausts.com
