Advice wanted - replacement cowls for 1974 GTR

I am having trouble finding the correct size cowls for my 1974 GTR.

Mine fit but one side is badly dented where a car side-wiped me last month.

I have seen the listing for the SIP "premium" quality cowls, but before I ship them over the Atlantic, I need to know they will correctly fit.   https://www.sip-scootershop.com/en/products/side+panels+engine+side+_751469j0

Or I would be happy to explore other options.  I tried Sprint cowls from a US store, which are supposed to fit my bike, but they were several cm too short and would not have attached to my bike's mounts.   

They need to be approximately 25 in (63.5 cm) long.

There seems to be a lot of confusion about the sizing for parts like these.

Many thanks for any advice, and if SIP could post dimensions, that would help!  

Best wishes from Buffalo, NY.

 

So I am puzzled...

SIP tells people NOT to email them, but to instead use this forum to seek out technical advice, and says their staffers monitor what is posted to give advice.....