Items such as these I would send with Evri as they will accept up to 120 cm even through the Ebay medium parcel size limit states 61 cm. I always exclude Royal Mail on my listings as Evri parcel shops are generally far more convenient to use than Post Offices. That said, I had an item listed that I stated as medium parcel even though it was closer to 80 cm, as normal I excluded Royal Mail, however the item sold to someone in the US via the Global Shipping Programme (GSP). What I didn't realise when listing, is that GSP orders only seem to get sent to the Ebay UK distribution hub by Royal Mail and I was provided a RM QR code for the Post Office, this firstly annoyed me as I don't like Post Offices but second concerned me because the parcel exceeded my understanding of Royal Mail's published parcel sizes. But when I got to the Post Office it was scanned and accepted with no question.
My interpretation of this was that orders made through Ebay appear to be honoured by Royal Mail/Post Office despite the dimensions not meeting the Royal Mail parcel spec - I think that the Ebay/Royal Mail contract clearly allows for more flexibility than Royal Mail/Post Office offer their own customers, this is both confusing as much as it might be useful. I'd still recommend opting for Evri as 65 cm is well below their 120 cm maximum.
