Sorry to read that Phil. Hope you get sorted in reasonable time to get to your event.
For all my "small" / everyday cars I have always purchased a Spacesaver spare. Might take up space in the boot, but it is a good "get one home".
The Morgan(s), Land Rovers &c have full sized spares...


Graham (G4FUJ)

Sold L44FOR 4/4 Giallo Fly
'11 MINI Countryman Cooper D All4
'90 LR 90 SW